Because of the universal appeal of the comics medium it is only natural that it has been used in many different ways to both put forth and criticize a variety of religious concepts and teachings.
Perhaps the most common form of religion in the comics medium is the adaptation of classic religious works or the biographies of religious personages. Usually these are created by followers of the relevant religious perspectives. Although sometimes a story or biography has reached such a level of popular consciousness that it is not necessarily published by any particular group or company.
Another increasingly popular way in which the comics medium connects with religion is with the retelling of religious motifs within a variant setting very similar to the way in which the comic series Fables and Greek Street has repackaged classic stories into an all new setting. Some examples of this would be Garth Ennis' The Chronicles of Wormwood and Vertigo's Testament.
One final way in which the comics medium intersects with religion is with comic material which is specifically intended to teach or preach a religious message. Sometimes this is directed towards a younger audience and sometimes it is intended for wide distribution such as the many brief tracts published by Chick Publications. Usually this material is published by a company which shares the particular religious view. But the medium can also be used to criticize religious organizations or doctrines.