In the Ayutthaya Period, Wat Rakhang Khositaram was the residence of the much revered intellectual patriarch (Si), who has an authority in the Tri-Pitaka and meditation.

Rama I thus intended to renovate the temple to restore its grandeur. The original resident hall and the reception hall were removed to be rebuilt near the image hall, to serve as the scripture halls. Along the borders were decked with blessing angels at intervals. Inside are murals painted on teak panels. The south portals are decorated with traditional scroll patterns. The eastern portal of the middle room and the balcony gates are woodcarving. The big scripture cabinets belonging to the Ayutthaya Period stand in the sleeping chamber and the reception hall. The traditional motif and the carving are believed to be the artwork of Rama II (then Prince Itsara Sunthon) and a woodcarving master from Ayutthaya.