The Music City Sisters are a missionary order of the Sisters of Perpetual Indulgence. If that doesn’t sound especially orthodox to you, you’re onto something. This order of nuns does not answer to the Church, and their art is nowhere near ecclesiastical. The sisters are increasing their visibility in Nashville with a regional art show hosted by OutCentral. Alphabet Art is brought to you by the letters “GLBTQIFP,” a sort of emblematic abbreviation for the various identity groups of the queer community. The Sisters of Perpetual Indulgence are a national order founded to fight for gay rights, practice safe sex outreach and raise money for AIDS awareness. Their tenets include “the promulgation of universal joy” and “expiation of stigmatic guilt.” The 24 works featured in the show go a long way toward that expiation. Meditating on themes of identity, they are challenging, thought-provoking and part of a good cause.