The Apostle Paul refers to our union with our spouse a mystery. While there are plenty of jokes that could follow, what he’s talking about is the nature of the spiritual union in marriage. He describes it as a husband and wife being glued together. He gives the example that we are one with our spouse as Christ is one with his church. He even goes so far as to say if a husband loves himself he’s loving himself. He doesn’t say it’s “like” loving yourself, he said it “IS” loving yourself.