Board Thread:Lore Discussion/@comment-92.251.228.132-20141108020915/@comment-177.34.181.193-20150904031133

They "worship" Sithis, the deity of chaos and personification of Padomay(the force of change).

Sithis was essential to the creation of everything that there is. His interplay with Anuiel, the deity of order and personification of Anu(the force of the non-changing) created Aurbis(the universe). In some way, what they do is necessary, since they are following Sithis, and Sithis, being one of the "creators" of the universe, does what is necessary. This in the context of contracts performed by the Black Sacrament.

They are also a guild of assassins that does minor contracts like every other. The difference is that they don't fail.