"There is no God but me the lonely, the imprisoned." (Bahā’u’llāh, Āthār-i Qalam-i A`lā (Canada: Mu’assisiyi Ma`ārif Bahā’ī, 1996), vol. 1, no. 39, p. 226.)
I don't like to speak for Bahaullah or the Bahai faith, but the image of a lonely or imprisoned "me" or "self" is a (also?) a mystical image of the soul longing for liberation or being (one) with God? Of course I have no idea how this was really meant by Bahaullah.