"...nor am I willing to accept an obscure line in Romans to be more defining of Christianity than the Sermon on the Mount."
Obama apparently doesn't remember that Jesus' Sermon on the Mount basically takes the Law of Moses and tightens up on it, not loosens it. So "You shall not kill," becomes, "You shall not kill the spirit of your fellow man, either." Likewise, "You shall not commit adultery," becomes, "You shall not even look on somebody with lust." And since homosexuality is condemned right along with adultery in Leviticus 18 and 20, had Jesus felt the issue necessary to address, it's only fair to think he would have tightened up on that law, too, not done a complete 180-degree moral turn and authorized "gay marriage."