That particular composition is from “The Bridal Chorus” of Richard Wagner’s opera Lohengrin. From my quick search of the Internet, I was unable to determine Wagner’s religious affiliation, if any, but there was no indication either that he was pagan. Jews object to using “Here Comes the Bride” at their weddings because Wagner was a notorious anti-Semite and a personal hero of Adolf Hitler. Catholics object on the grounds that the song is secular in nature and should therefore be excluded from a religious liturgy. This isn’t set in stone however; some Catholic churches are more lenient than others on this and will allow classical music.
