Introduction

The significance of light in Islamic architecture, particularly in the construction of mosques, is deeply rooted in theological, philosophical, and aesthetic traditions. The Quran explicitly mentions light as a divine attribute: "Allah is the Light of the heavens and the earth" (Quran 24:35). This concept has influenced Islamic architects and philosophers throughout history, shaping the spatial experience of worship. Despite this, contemporary mosque architecture has largely shifted toward a more quantitative and functional approach, neglecting the qualitative and symbolic dimensions of natural light. The present study aims to bridge this gap by identifying the fundamental qualities of light, as derived from Quranic texts, and analyzing their application in Iranian-Islamic mosques. Drawing upon the interpretations of Islamic scholars and philosophers, seven core principles of qualitative light were extracted: existential authenticity, existential hierarchy, justice, abstraction, permanence, guidance, and signification (Bamanian & Nikodel, 2014). These principles were then mapped onto architectural features within historic mosques to evaluate how light contributes to the creation of a spiritually enriched environment. The study focuses on five prominent Iranian mosques—Sheikh Lotfollah Mosque, Imam Mosque, Hakim Mosque, Rahim Khan Mosque, and Seyyed Mosque—due to their exceptional use of natural lighting to enhance spiritual experiences. Employing a descriptive-analytical research method, this study integrates field investigations with an extensive review of Islamic texts and architectural sources to establish a theoretical framework for the presence of light in sacred spaces.

The research finds that the application of qualitative light principles in mosque architecture enhances the perception of divine unity and spiritual ascension. The existential authenticity of light is represented through its direct and unaltered penetration into mosque interiors, signifying a connection between the material and the divine (Bamanian, 2009). The principle of existential hierarchy manifests in the strategic layering of light sources, guiding worshippers' visual experience from the prayer hall to the dome, reinforcing the concept of divine transcendence. Justice, as a principle, is observed in the equitable distribution of light across the mosque, ensuring that no section remains in complete darkness, reflecting the Islamic philosophical notion of divine justice (Vahabi & Mousavi Zadeh, 2006). The principle of abstraction is realized through the dematerialization of architectural elements, where light dissolves rigid structural boundaries, creating an ethereal atmosphere conducive to spiritual contemplation. Permanence is expressed through the continuous interplay of natural light throughout the day, symbolizing the eternal presence of divine illumination. The principle of guidance is evident in how light is directed toward the mihrab, aiding worshippers in orienting themselves toward prayer. Lastly, the principle of signification is observed in the intricate play of shadows and light patterns on surfaces, reinforcing the metaphorical representation of divine knowledge and wisdom (Amoli, 1989). These findings suggest that the strategic use of natural light in mosque architecture does more than serve functional lighting needs; it actively shapes the spiritual and cognitive experiences of worshippers.

Several previous studies have explored the relationship between light and sacred architecture, but they have often remained within philosophical or historical discussions without providing empirical frameworks for analysis. Houmani-Rad and Sharafi (2015) investigated the ergonomics of daylight in mosques, finding that natural light significantly affects user engagement and worship focus (Houmani-Rad & Sharafi Nafar, 2015). Akbari Baseri and Gholipour (2014) explored the symbolic dimension of colored light in sacred Iranian spaces, emphasizing its role in conveying hierarchical spatial experiences (Akbari Baseri et al., 2014). Similarly, Houmani-Rad and Tahbaz (2014) examined how variations in window forms and shading devices influence the quality of daylight within mosque interiors (Houmani-Rad & Tahbaz, 2014). Bamanian and Nikodel (2014) assessed the effectiveness of different light sources, particularly in Qajar-era mosques in Tehran, finding that wooden lattice windows (shabak) were the most effective in maintaining a balanced lighting scheme (Bamanian & Nikodel, 2014). More recent studies, such as Wardono and Wibisono (2013), demonstrated that top-down concealed daylighting methods elicited stronger emotional responses from users, further confirming the psychological impact of controlled natural light (Wardono & Wibisono, 2013). The cumulative insights from these studies reinforce the argument that qualitative light principles, when applied methodically, can enhance the spiritual and psychological effects of mosque spaces.

The methodology of this study combines qualitative and quantitative approaches to assess the spiritual impact of light in mosque architecture. The study utilized observational analysis, field surveys, and computational lighting simulations to measure light distribution and intensity across different mosque spaces. To empirically validate the theoretical framework, a questionnaire was designed based on the extracted qualitative light principles. The questionnaire, structured on a Likert scale, was distributed among 430 mosque users, including worshippers, architects, and religious scholars. The reliability of the questionnaire was confirmed through Cronbach's alpha (α = 0.88), indicating a high degree of internal consistency. The normality of the data was assessed using the Shapiro-Wilk and Kolmogorov-Smirnov tests, both of which confirmed that the dataset followed a normal distribution (Tahbaz et al., 2013). Findings from the survey revealed that users perceived the highest degree of spiritual presence in spaces where natural light was both dynamically controlled and hierarchically structured. The results also indicated that the placement of openings, particularly their height and orientation, played a crucial role in shaping the sacred experience. The Sheikh Lotfollah and Imam Mosques were rated highest in terms of achieving an optimal balance between functional and symbolic lighting, whereas the Hakim and Rahim Khan Mosques demonstrated moderate success in integrating qualitative light principles. The Seyyed Mosque, although exhibiting strong daylighting strategies, was found to be less effective in conveying a sense of ascension and divine abstraction.

The implications of this research extend beyond historical mosque architecture and offer insights for contemporary mosque design. Modern mosques often prioritize artificial lighting over natural solutions, leading to a diminished spiritual ambiance. The study recommends the integration of adaptive daylighting systems that align with the qualitative light principles outlined in Islamic teachings. Architects should consider incorporating multi-layered fenestration, strategic placement of openings, and the controlled use of reflective surfaces to maximize the dynamic interplay of natural light. Additionally, computational modeling tools such as Radiance can be employed to simulate the effects of daylighting before construction, ensuring that contemporary mosque designs adhere to spiritual and psychological considerations (Sanusi Hassan & Arab, 2013). Future research could explore how advanced materials and smart lighting technologies can be harmonized with traditional light principles to create immersive and spiritually enriching worship environments.

In conclusion, this study provides a comprehensive framework for understanding and applying qualitative light principles in mosque architecture. By integrating Quranic interpretations with architectural analysis, it highlights the indispensable role of natural light in shaping sacred spaces. The research underscores that the strategic deployment of light is not merely an aesthetic concern but a theological and experiential necessity in mosque design. The findings reinforce the idea that mosques should not only function as places of worship but also as spaces that actively facilitate spiritual transcendence through their architectural composition. Through the seven qualitative principles derived from Quranic texts, this study establishes a foundation for rethinking contemporary mosque lighting strategies. By advocating for the revival of traditional daylighting techniques, it presents a path toward creating mosque environments that are not only visually captivating but also deeply resonant with Islamic spiritual philosophy.