The present paper analyzes the spatial composition of Hosios Loukas with the theme and layout of the paintings, focusing on the relationship between the tomb and the paintings (Fig.1, Fig.2). Loukas' relics lie in “Space Λ” between the Church of the Panaghia and the Katholikon (Fig.4, Fig.12). Loukas’ tomb (sarcophagus) is located in the north arm of the crypt, beneath his relics (Fig.5, Fig.8). The tomb is visible in front of the south portal of the crypt (Fig.7), but the tomb (relics) is not easily accessed from the west portals of the Church of the Panaghia and the Katholikon. “Space Λ” rests in the gap between the two churches. The importance of Loukas’ tomb is unclear due to its architectural aspect. However, this tomb was presumably connected to all the churches with the layout of the paintings. This paper describes how the layout of the paintings of Hosios Loukas gives meaning to the architectural space. This church has enormous implications for determining how a holy space was constructed.

I surveyed Hosios Loukas in September 2012 and August 2018, and created three-dimensional images, interior elevations (Fig.13, Fig.14, Fig.15, Fig.16 upper middle, middle left, middle right, lower middle), an interior view of the ceiling (Fig.16 middle), and isometric drawings (Fig.16 upper left, upper right, lower left, lower right). I then analyzed the spatial composition of the paintings, focusing on the south portals of the Eukterion and the Church of Saint Barbara, the paintings in the Katholikon’s naos, narthex, northwest chapel, and “Space Λ,” and the location of Loukas' tomb to clarify the significance of the architectural space with the theme and layout of the paintings.

In the second half of the 10th century, the Church of Saint Barbara and the Eukterion had south portals (Arrow 1 and 2 in Fig.3), Loukas' tomb was venerated in the north arm of the Eukterion or the crypt (Arrow 1 in Fig.5). In the first half of the 11th century, based on the construction and connection of the Church of the Panaghia and the Katholikon, and the layout of the paintings, the old space, consisting of the Church of Saint Barbara and the Eukterion from the south portal to the north of Loukas’ tomb, overlapped with the new space after the translation of Loukas’ relics. This new space encompassed the Church of the Panaghia and the Katholikon from the west narthex to the east apse (Arrow 1 in Fig.4). The Katholikon’s naos, narthex, northwest chapel, and “Space Λ” are connected to the Christian paintings; Loukas was painted near his tomb, and Christ and the Virgin are painted opposite or behind Loukas (Line 1 in Fig.4). This establishes a three-dimensional Byzantine religious space centered on Loukas’ tomb.

The Church of Saint Barbara and the Eukterion were separated, with a space established in the two churches to venerate Loukas’ tomb from the south to the north. When the Church of the Panaghia and the Katholikon were constructed, the space for Loukas’ tomb changed into a subordinate space. However, a holy space from the west to the east was devised with the layout of the paintings that connect to Loukas’ tomb to represent donor prayers that invoke Loukas’ grace. His tomb remains as the center of the two churches to this day.