"The blessing of same-sex marriages and same-sex unions is an issue about which Christian churches are in ongoing disagreement. These disagreements are primarily centered on the interpretation of various scripture passages related to homosexuality, and in some churches on varying understandings of homosexuality in terms of psychology, genetics and other scientific data. While various Church bodies have widely varying practices and teachings, individual Christians of every major tradition are involved in practical (orthopraxy) discussions about how to respond to the issue."https://en.wikipedia.org/wiki/Blessing_of_same-sex_unions_in_Christian_churches

There are, across the world, thousands of Christian churches which bless (sanction) same sex marriage.  There are thousands which don't.  Obviously, your church and your personal beliefs represent the "don't" category.

cont.