As someone who unknowingly proselytizes at times, he likely isn't aware of how his words appeared. His words if said to a Christian would make sense, but to everyone else they come off as condescending.

If you tell him how made you feel awkward and doubt the sincerity of his friendship, he probably will accept what you have to say.

As a Christian who does agree with the decision, I get annoyed when non-Christians think all Christians are either like Huckabee and Ben Carson or 'love the sinner, hate the sin'.

It's possible that he read the post your Facebook friend made and felt slighted that he is a more progressive Christian and had his faith belittled.

If you have a discussion about his frustration at the blog post and he isn't accepting of your explanation of how you felt by his text, then you may have just put the friendship on hold.