“Baking a cake to celebrate the wedding of a same-sex couple is an offense to God.”

Bull-FUCKING-shit.   Offending God is not a real thing.  It is a make-believe superstition without a shred of substance.  There is no evidence any of the currently popular gods even exists, so I do not give a fiddler’s flying fuck about whether your imaginary friend is offended.  He’s YOUR imaginary friend, and YOU imagined it, so YOU deal with it.  Not my fault you don’t have a better imagination to make a nicer imaginary friend.