Dont get it.....?

So let me say that my father is an Episcopalian priest......This is what I dont get.....My cousin has recently came out of the closet, she and her partner have been "roomates" for many years, they have decided to adopt a baby. My father was appalled at this. Isnt he, as a priest supposed to be "all accepting"? I said to him that 2 people who have shown devotion to eachother, that want to give a baby in need of a good loving home, just that, a good loving home, that it seems strange to me that he would find it sinful. I dont get all the judgement that goes along with religion.......