Although not outright banned, the idea of homosexual couples kissing in a religious site is wholeheartedly frowned upon by more than a few factions; take the photo series titled Trialogo by Gonzalo Orquin, a photographer hailing from Seville, Spain, as an example. It captures such loving pairs at the heart of Catholic churches. Sadly, an exhibit of the images was legally threatened and ultimately shut down by the Vatican on the grounds that it was unconstitutional.
Trialogo by Gonzalo Orquin was deemed offensive in the eyes of the Catholic church, which went on further to say how they would "infringe upon the advancement of man in the particular place for the expression of faith." Yet they will be displayed in New York's Leslie+Lohman Museum this May.