An Assessment of the Impact of Design Elements on the Liturgical Space of Church Buildings: Using Churches in the North of Iraq as a Case Study

Abstract

Liturgical space represents the embodiment of Christian theology in church buildings, encompassing both physical and metaphysical aspects. This space carries holiness and sacredness through a set of architectural elements that create sacred and profane zones within the church architecture. For centuries, design elements have shaped the form of Eastern churches in Iraq. This research aimed to answer the following question: what does a participant see at first glance in the liturgical space of a church building? This paper revisits the impact of design elements on the liturgical space of Eastern churches. The research methodology involved analyzing qualitative data using visual attention software (VAS) 3M, version 2024, to examine eye-tracking data and identify what visitors first noticed when entering these church interiors in Mosul, Iraq. The results highlight the variations and dominance of specific design elements in their impact on Eastern churches. The conclusions emphasize the importance of scientifically based restoration for the perception of design elements in these churches.

1. Introduction

Christian worship is a cosmic liturgy that embraces both heaven and earth. The Christian liturgy gives the spirit and the representation of heaven and earth in the interiors of church buildings, which, in turn, represents the vision of the theology to the visitors [1,2]. Christian churches in the Middle East represent architectural samples that carry a divine symbolism and are good examples of the spreading of the Christian religion in the East. Previous studies have attempted to specify the main variables related to liturgical space. These studies related to liturgical space clarified two major types: The first type represents a description of the church parts and furniture from a liturgical point of view [2,3,4]. The second type represents a description of the design elements from a constructional and architectural point of view [4,5,6]. The research gap is clarified as a lack of knowledge about the impact of design elements on the liturgical space of churches of the East. The research hypothesis proposes that vertical elements have a high impact on the liturgical space of the churches in the north of Iraq. The research methodology was conducted by analyzing the qualitative data, using visual attention software (VAS) 3M to analyze the eye-tracking data and what viewers saw at first glance when visiting the interiors of churches in the city of Mosul, Iraq. The researchers used an inductive reasoning approach with regard to observation and the analysis of knowledge.

Space is a prime ingredient in a designer’s palette and the quintessential element of interior design. Through the volume of space, participants see forms, hear sounds, feel gentle breezes and the warmth of the sun, and smell the fragrances of flowers in bloom. Space inherits the sensual and aesthetic characteristics of the elements in its field [5]. The objective of this study was to assess the elements of design that are most seen by participants in the liturgical space of church buildings. In this study, nine churches in the city of Mosul were selected as notable cases in Iraq. The case study was evaluated using a software tool (visual attention software) to test the theoretical frame vocabularies on the study samples. This study endeavored to highlight the most-seen elements to be used as a model in the field of liturgy and architecture. The main approach discussed in this paper will begin with an examination of space elements, followed by a discussion of liturgical parts (see Figure 1).

1.1. Directions of Lines

Horizontal lines represent the floors and ceilings in architectural forms. There are many types of ceilings, including beam and lacunar ceilings, coffer and camp ceilings, and cove and plafond ceilings [6]. Vertical lines, Walls serve as the primary external covering for churches, supported by different types of piers [7]. Pillars, a key element of architectural and structural design, provide vertical support and often feature a base and capital. The pilaster strip, a vertical structural component, consists of a protruding half-column or half-pillar embedded into a wall [8]. Curved lines are represented by arches, which are curved structures used to span openings and are largely supported by axial compression to bear vertical loads [6]. A simple extended arch vault is known as a barrel vault or tunnel vault. A more complex vault results from the right-angle intersection of two barrel vaults [9]. The use of barrel vaults built from cut stone blocks became widespread during the Middle Ages [7]. A dome is a particular kind of covering created when an arch rotates around a central vertical axis, often featuring a circular base. There are many types of domes with various details, such as pendentive domes with hoop lines; lanterns; cupolas; tambours; and drum and Tholobate domes [6].

Sloping diagonal lines indicate motion and activity. These oblique or diagonal lines are only maintained by unique methods of gravitational force resistance and are perpetually in transition between the vertical and horizontal orientations that tolerate gravity [10]. Repeating flooring strips that rise upward, known as stairs, can be free-standing or linked to one or more walls [11]. Stairs may be built from any material, including reinforced concrete, metal, and brick. The range of practicable metric shapes has led to the development of various essential types of stairs, such as rectilinear ramps, wellholes, helicoidal stairs, spiral stairs, and others [8].

1.2. Shapes and Forms

There are three primary categories of forms: natural shapes, geometric shapes, and abstract shapes. Natural shapes originate from the human body or anything else found in the natural world. Nature has a wide variety of geometric forms, including hexagons, squares, triangles, and specific leaf forms seen in trees and shell formations. Abstract shapes are those whose basic characteristics have been adjusted to accentuate them without reference to a realistic representation [12]. Form refers to the shape and structure of something [5]. Basic forms can be divided into three groups: geometric forms, triangular forms, and curved forms. Geometric forms are the most common in architecture and interior design; triangular forms have a pointed appearance; and curved forms include cylinders, cones, and circles [11].

A doorway is a structure made up of two uprights, or jambs, whose axes can be either vertical or inclined, serving the static function of supporting their own weight and any thrusts transmitted from structures above them. On top of an architrave, which forms a rectangular trilithic doorway, or over which an arch springs, is a transverse element of closure. A window is a hole drilled into a building’s wall that lets light and air in while providing a view of the outside. The window and the facade’s conformation are closely related [8].

1.3. Churches of the East

The term “Christian Church” refers to the collective group of all Christians [13]. Most English translations of the New Testament generally use the word “church” as a translation of the Ancient Greek term “Eκκλησία” (transliterated as “ecclesia”) found in the original Greek texts, which generally meant an “assembly” [14]. A Nestorian church is traditionally a rectangular building with one or three naves, built of stone or fired clay. The choir is oriented toward the east, where the sun rises and whence Christ will appear on Judgment Day (Matt 24:27). The entrance doors for people are found on the southern wall. Sometimes there are two doors, one for each sex. The interior is divided into three parts along both axes. To the east and in the center is the Holy of Holies (and the choir), which symbolizes heaven and can only be entered by clergy of the rank of deacon or above. The Holy of Holies is raised on three levels. A stone or wooden choir screen, with one to three arches, divides the nave from the choir; it corresponds to the iconostasis of Orthodox churches. Today, the choir screen is rarely seen, but the curtain, as in Syrian Orthodox churches, remains. Between the nave and the choir is the qostroma, which means vestibule, raised up by three steps. In earlier times, the center of the nave featured a rectangular or horseshoe-shaped platform called the bema, which symbolized Jerusalem as the center of Jesus’s life [4] (see Figure 2).

The forecourt of an early Christian church was flanked or surrounded by porticos [6]. The courtyard occasionally had a fountain, cistern, or well in the middle [3]. Numerous significant churches in the Eastern Mediterranean were highlighted by grand entrances [15]. The next phase is the nave; the word might alternatively have come from the Greek word “naos”, which means “the boat” [3]. The naos can have a variety of shapes, including square, octagonal, rectangular, cruciform, and circular shapes. Typically, a colonnade or arcade of some kind with vertical supports in the form of columns or piers would surround the nave, wholly or in part [16] (see Figure 3).

The apse is a semicircular or polygonal architectural extension utilized in a church’s east sanctuary [6]. The apse symbolizes the early Christian architectural theology’s contrast between the profane west and hallowed east ends [15]. Additionally, the sanctuary serves as a representation of “the heaven of the heavens”, or God’s abode, and its orientation carries symbolic meaning [19]. There are two different forms of apses: the triple-apse form and the single-apse form, with or without side chambers on each side [20]. The bema (βῆμα in Greek, meaning step or pace) forms the elevated platform situated in front of the apse and houses the Holy Table. The complex screen or templon evolved into a highly ornamental icon screen (iconostasis) [16].

The iconostasis is a screen or barrier on which icons are placed, dividing the bema from the nave of an Eastern church. In early Christian churches, the ambo, also known as an ambon, was one of two elevated platforms from which the Gospels or Epistles were read or chanted [6]. The word “pastophoria” first appears in the Old Testament, referring to the temple of Solomon’s treasury and priests’ apartments. The diakonikon surrounds the center bay of the bema and Holy Table [16]. The interlocking arcade is a blind arcade made up of arches resting on opposing supports and overlapping in series where they intersect. The galleries or upper level of a church run along the outer wall of the structure [6]. They are located either above the side aisles or the narthex and open completely into the nave area. It is more likely that the galleries were for the catechumens and other special groups distinct from the believers, despite some claims to the contrary. Men exclusively filled the floor of the naos [16] (see Figure 4).

2. Materials and Methods

This research was qualitative. Data were collected from the literature, via observation, and by surveying the ancient churches. Documentation was conducted by taking photos and measurements. The local architectural samples of ancient churches were documented by the researchers using a galaxy A32 mobile phone camera 64 MP version 13.1.01.1 (installed on a tripod stand, with the camera positioned 1.8 m above ground level. Additional data were collected from architects, experts in the history of architecture, books, research, and journal articles. The documentation and collected data of the ancient churches were transformed into architectural drawings using the latest version of the AUTOCAD 2024 program. The ancient architectural samples were analyzed using the visual attention software (VAS) 3M, having purchased the latest version. According to the legend attached in (Figure 5), the translation of the heat map into a semantic differential scale (from 1 to 5) was performed as follows: from 0 to 20% equals 1, (dark blue zone to blue); from 20 to 40% equals 2, (blue zone to cayenne); from 40 to 60% equals 3, (yellow zone to orange); from 60 to 80% equals 4, (orange zone to red); and from 80 to 100% equals 5, (red zone to dark red) (see Figure 5).

The application was used to measure eye tracking for the most seeable elements of a church building at first glance while visiting the interiors of the church building. In order to navigate the world around us, human brains have developed shortcuts to pre-select the most relevant visual information at first glance. VAS leverages these biological shortcuts to simulate how viewers are likely to see content. VAS simulates the first-glance phase before gender, age, culture, and viewer tasks impact the viewer’s attention. If viewers see content during this first glance, it is more likely that they will engage with it consciously later. This tool was used in three stages: selecting the work to be tested to know what viewers were likely to see at first glance, analyzing the work, and obtaining results [23] (see Figure 6). The analyzed data were organized in a table to complete the statistical analysis using the latest version 29 of the SPSS statistical program. The VAS analysis of the samples in this study, according to the vocabulary obtained from the theoretical framework of the liturgical space of churches of the East in northern Iraq, is clarified in the graphical analysis forms attached in Appendix A.

Case Study

The samples in this study were selected from the 3rd century and later in order to obtain the greatest variety possible of design elements in liturgical spaces during ancient times and throughout the different civilizations that successively built in the cities of northern Iraq. The case study included samples of churches of the East in the city of Mosul and the plains of Nineveh in the north of Iraq. The churches selected belong to different religious sects, including the Catholic and Syriac Orthodox Churches (see

Table 1. The main and sub-vocabularies obtained from the theoretical framework.

Vocabulary		Sub-Vocabulary
Liturgical space	Design elements	Horizontal elements	Floor and ceiling lines
		Vertical elements	Bearing walls and partitions
		Curved elements	Arches, openings, and domes
		Diagonal elements	Stairs
		Shapes	Natural, geometric, and abstract shapes
		Forms	Geometric and curved forms
	Church parts	Entrances of the church
		Nave and aisles
		The east end	Apse and altar and the bema
			Pastophoria and diakonikon
		Galleries
		Partitions	Iconostasis and ambo
		Arcades	Interlocking arcades

). All the churches were in good structural condition and contained the main parts mentioned in the theoretical framework (see

Table 2. The samples in this study.

No.	Sample Name	Plan	Interior Space
1	Our Lady of the Harvest Monastery Church, ca. 1857 CE, Alqosh, Nineveh Plains, Iraq
2	The Orthodox Syriac Church of St. Shmoni, reconstructed in 1890 CE, Bashiqa, Nineveh Plains, Iraq
3	The Catholic Church of St. Kyriakos, reconstruction date in 1944 CE, Batnaya, Nineveh Plains, Iraq
4	The Catholic Church of St. Georges, ca. 1681 CE, Alqosh, Nineveh Plains, Iraq
5	The Church of Saints Peter and Paul, Tilkef, Nineveh Plains, Iraq
6	The Syriac Catholic Church of St. Thomas, ca. 1859 CE, Mosul, Iraq
7	The Syriac Orthodox Church of St. Thomas, Mosul, Iraq
8	The Church of the Holy Heart of Jesus, ca. 1911 CE, Tilkef, Nineveh Plains, Iraq
9	The Orthodox Syriac Church of the Virgin Mary, ca. 1890 CE, Bartilla, Nineveh Plains, Iraq

).

3. Results

The value of R squared from the model summary was 0.997, which means that the seven elements of design achieved a percentage of 99.7% based on the change in the dependent variable (the Syriac Catholic Church of St. Thomas in Mosul). This percentage represents a high interpretability rate. Next came the Church of the Holy Heart of Jesus Christ with a percentage of 98.1%, both of the Mart Shmoni and St. Thomas Orthodox Churches with a percentage of 96%, the Church of the Lady Monastery with a percentage of 93.6%, the St. Georges Catholic Church with a percentage of 92.9%, the St. Kyriakos Catholic Church with a percentage of 87.6%, the Virgin Mary Orthodox Church with a percentage of 86.9%, and, finally, the Church of St. Peter and Paul with a percentage of 66.2%, as clarified in Figure 7.

The significant value for each church is compared with (0.05) for the best strength of impact. In the Syriac Catholic Church of St. Thomas, the significant value carried a high impact because it was less than the assumed significant value (0.05). Next came the Catholic Church of St. Kyriakos with a value of 0.006, the Catholic church of St. Georges with a value of 0.012, the church of the Holy Heart of Jesus Christ with a value of 0.014, the Church of St. Peter and Paul with a value of 0.016, the church of the Lady Monastery with a value of 0.022, the Orthodox Church of the Virgin Mary with a value of 0.031, and, finally, both of the Orthodox Churches of Mart Shmoni and St. Thomas with a value of 0.041, as clarified in (Figure 8).

According to the analysis of the visual attention software, the probability of visual fixation within 3–5 s for each of the elements of design in the liturgical space of the church buildings had a high impact on the Syriac Catholic Church of St. Thomas. The sig. values for each of the elements of design were as follows: the visual fixation for the ceilings, domes, and details had the highest rate, with a sig. value of 0.000 for each of them; the visual fixation for the arches, shapes, and forms came next, with a sig. value of 0.002 for each of them; and last, the planes obtained a sig. value of 0.034 (See

Table 3. The heat maps and attraction regions of the Catholic Church of St. Thomas, Mosul, Iraq.

Shot 1: Toward the apse from the nave (Camera 1).	Shot 2: Toward the apse from the right aisle (Camera 2).	Shot 3: Toward the apse from the left aisle (Camera 3).		Shot 4: Toward the west end from the nave (Camera 4),
Shot 5: Toward the west end from the right aisle (Camera 6).	Shot 6: Toward the west end from the left aisle (Camera 5).	Shot 7: Through the apse, Zone 1 (Camera 7).		Shot 8: Through the apse, Zone 2 (Camera 8).

Note: For the landscape shots, the upper pictures represent the heat maps, and the lower pictures represent the attraction regions; for the portrait shots, the left pictures represent the heat maps, and the right pictures represent the attraction regions.

and Figure 8 and Figure 9).

According to the analysis of the visual attention software, the probability of visual fixation within 3–5 s for each of the elements of design in the liturgical space of the church building had less impact in the Syriac Orthodox Church of St. Thomas. The sig. values for each of the elements of design were as follows: the visual fixation of the details had a high impact, with a sig. value of 0.020; next came the visual fixation of each of the forms, shapes, domes, planes, and ceilings, with sig. values of 0.038, 0.426, 0.439, 0.597, and 0.741, respectively; and finally, the visual fixation of the arches obtained a sig. value of 0.956 (see

Table 4. The heat maps and attraction regions of the Syriac Orthodox Church of St. Thomas, Mosul, Iraq.

Shot 1: Toward the apse from the nave (Camera 1).	Shot 2: Toward the apse from the right aisle (Camera 2).	Shot 3: Toward the apse from the left aisle (Camera 3).		Shot 4: Toward the west end from the nave (Camera 4).
Shot 5: Toward the west end from the right aisle (Camera 6).	Shot 6: Toward the west end from the left aisle (Camera 5).	Shot 7: Through the apse, Zone 1 (Camera 7).		Shot 8: Through the apse, Zone 2 (Camera 8).

Note: For the landscape shots, the upper pictures represent the heat maps, and the lower pictures represent the attraction regions; for the portrait shots, the left pictures represent the heat maps, and the right pictures represent the attraction regions.

and Figure 8 and Figure 10).

Additionally, the probability of visual fixation within 3–5 s had less impact in the Orthodox Church of Mart Shmoni. The sig. values for each of the elements of design were as follows: the visual fixation of the forms had a high impact, with a sig. value of 0.009; next came the visual fixation of each of the details, ceiling, shapes, domes, and planes, with sig. values of 0.020, 0.023, 0.196, 0.344, and 0.527, respectively; and finally, the visual fixation of the arches obtained a sig. value of 0.582 (see

Table 5. The heat maps and attraction regions of the Orthodox Syriac Church of St. Shmoni, Bashiqa, Iraq.

Shot 1: Toward the apse from the nave (Camera 1).	Shot 2: Toward the apse from the right aisle (Camera 2).	Shot 3: Toward the apse from the left aisle (Camera 3).		Shot 4: Toward the west end from the nave (Camera 4).
Shot 5: Toward the west end from the right aisle (Camera 6).	Shot 6: Toward the west end from the left aisle (Camera 5).	Shot 7: Through the apse, Zone 1 (Camera 7).		Shot 8: Through the apse, Zone 2 (Camera 8).

Note: For the landscape shots, the upper pictures represent the heat maps, and the lower pictures represent the attraction regions; for the portrait shots, the left pictures represent the heat maps, and the right pictures represent the attraction regions.

and Figure 10 and Figure 11).

Finally, according to the analysis of the visual attention software, the probability of visual fixation within 3–5 s for each of the elements of design in the liturgical space of the church buildings had varying impacts in the rest of the churches, starting with the Catholic Church of St. Kyriakos, with a sig. value of 0.006; next, the Church of St. George, with a sig. value of 0.012; the Church of the Holy Heart of Jesus, with a sig. value of 0.014; the church of St. Paul and Peter, with a sig. value of 0.016; and finally, the Church of the Lady Monastery with a sig. value of 0.022 (see Figure 12; the other details are clarified in

Table A1. The heat maps and attraction regions of the Monastery Church of Our Lady of Harvest, Alqosh, Iraq.

Shot 1: Toward the apse from the nave (Camera 1).	Shot 2: Toward the apse from the right aisle (Camera 2).	Shot 3: Toward the apse from the left aisle (Camera 3).		Shot 4: Toward the west end from the nave (Camera 4).
Shot 5: Toward the west end from the right aisle (Camera 6).	Shot 6: Toward the west end from the left aisle (Camera 5).	Shot 7: Through the apse, Zone 1 (Camera 7).		Shot 8: Through the apse, Zone 2 (Camera 8).

Note: For the landscape shots, the upper pictures represent the heat maps, and the lower pictures represent the attraction regions; for the portrait shots, the left pictures represent the heat maps, and the right pictures represent the attraction regions.

,

Table A2. The heat maps and attraction regions of the Catholic Church of St. Kyriakos, Batnaya, Iraq.

Shot 1: Toward the apse from the nave (Camera 1).	Shot 2: Toward the apse from the right aisle (Camera 2).	Shot 3: Toward the apse from the left aisle (Camera 3).		Shot 4: Toward the west end from the nave (Camera 4).
Shot 5: Toward the west end from the right aisle (Camera 6).	Shot 6: Toward the west end from the left aisle (Camera 5).	Shot 7: Through the apse, Zone 1 (Camera 7).		Shot 8: Through the apse, Zone 2 (Camera 8).

Note: For the landscape shots, the upper pictures represent the heat maps, and the lower pictures represent the attraction regions; for the portrait shots, the left pictures represent the heat maps, and the right pictures represent the attraction regions.

,

Table A3. The heat maps and attraction regions of the Catholic Church of St. Georges, Alqosh, Iraq.

Shot 1: Toward the apse from the nave (Camera 1).	Shot 2: Toward the apse from the right aisle (Camera 2).	Shot 3: Toward the apse from the left aisle (Camera 3).		Shot 4: Toward the west end from the nave (Camera 4).
Shot 5: Toward the west end from the right aisle (Camera 6).	Shot 6: Toward the west end from the left aisle (Camera 5).	Shot 7: Through the apse, Zone 1 (Camera 7).		Shot 8: Through the apse, Zone 2 (Camera 8).

Note: For the landscape shots, the upper pictures represent the heat maps, and the lower pictures represent the attraction regions; for the portrait shots, the left pictures represent the heat maps, and the right pictures represent the attraction regions.

,

Table A4. The heat maps and attraction regions of the Catholic Church of St. Peter and Paul, Tilkef, Iraq.

Shot 1: Toward the apse from the nave (Camera 1).	Shot 2: Toward the apse from the right aisle (Camera 2).	Shot 3: Toward the apse from the left aisle (Camera 3).		Shot 4: Toward the west end from the nave (Camera 4).
Shot 5: Toward the west end from the right aisle (Camera 6).	Shot 6: Toward the west end from the left aisle (Camera 5).	Shot 7: Through the apse, Zone 1 (Camera 7).		Shot 8: Through the apse, Zone 2 (Camera 8).

Note: For the landscape shots, the upper pictures represent the heat maps, and the lower pictures represent the attraction regions; for the portrait shots, the left pictures represent the heat maps, and the right pictures represent the attraction regions.

,

Table A5. The heat maps and attraction regions of The Church of the Holy Heart of Jesus, Tilkef, Nineveh Plains, Iraq.

Shot 1: Toward the apse from the nave (Camera 1).	Shot 2: Toward the apse from the right aisle (Camera 2).	Shot 3: Toward the apse from the left aisle (Camera 3).		Shot 4: Toward the west end from the nave (Camera 4).
Shot 5: Toward the west end from the right aisle (Camera 6).	Shot 6: Toward the west end from the left aisle (Camera 5).	Shot 7: Through the apse, Zone 1 (Camera 7).		Shot 8: Through the apse, Zone 2 (Camera 8).

Note: For the landscape shots, the upper pictures represent the heat maps, and the lower pictures represent the attraction regions; for the portrait shots, the left pictures represent the heat maps, and the right pictures represent the attraction regions.

and

Table A6. The heat maps and attraction regions of The Orthodox Syriac Church of the Virgin Mary, Bartilla, Nineveh Plains, Iraq.

Shot 1: Toward the apse from the nave (Camera 1).	Shot 2: Toward the apse from the right aisle (Camera 2).	Shot 3: Toward the apse from the left aisle (Camera 3).		Shot 4: Toward the west end from the nave (Camera 4).
Shot 5: Toward the west end from the right aisle (Camera 6).	Shot 6: Toward the west end from the left aisle (Camera 5).	Shot 7: Through the apse, Zone 1 (Camera 7).		Shot 8: Through the apse, Zone 2 (Camera 8).

Note: For the landscape shots, the upper pictures represent the heat maps, and the lower pictures represent the attraction regions; for the portrait shots, the left pictures represent the heat maps, and the right pictures represent the attraction regions.

and Figure A1, Figure A2, Figure A3, Figure A4, Figure A5 and Figure A6 in Appendix A).

4. Conclusions

The historic church buildings in the north of Iraq are important as a rich part of the fabric of the old city. Management and restoration processes based on scientific resources have represented a challenge throughout the ages. This study investigated the perception of liturgical space based on analyzing those spaces using computer software. This study concludes that scientific restoration processes have a high impact on the realization of liturgical spaces. This conclusion is based on the results of the Catholic Church of St. Thomas. Good scientific restoration and management in the engineering process were essential in this church.

This study concludes that the research hypothesis is denied, and the shapes and use of accessories and additional symbolic details have the most impact on achieving visual fixation in a liturgical space. This conclusion is essential because it concentrates on the symbols used in churches. These symbols have theological connections with the liturgy and architecture. The planes feature in the second stage of visual fixation, and then come the other elements including the ceilings, arches, forms, domes, and details, and the reasons for this in churches of the East include the use of additional accessories and shapes, the materials used in the interior of the church buildings, the little use of lighting because of economic considerations, and the scale of the buildings, all of which are factors that prevent the eye from tracking the mentioned elements of design.

Regarding comment (EE133), the attention is drawn to non-structural components such as forms and shapes, such as the cross, in Eastern churches.

5. Recommendations

According to what was explained in the conclusion, the researchers recommend generating a detailed model for the elements of a church building, clarifying the most-seen elements based on the findings of this research, and applying them in the management and restoration processes of historical churches and also in the building of new churches.