The Blue Chapel is a part of a complex consisting of the chapel and courtyard, atrium According to P. M. Bikai the militarry barrack of the late fifth century was converted into a Christian chapel. It was small chapel which served rather for private ceremonies at the bishop`s residence or some welthy member of the local society.
Sources:
- Patricia Maynor Bikai, "The Churches of Byzantine Petra". Near Eastern Archaeology. 65 (4): 2002, 271–27 -https://www.jstor.org/stable/3210859
