I recently used that phrase on FaceBook, and was disappointed at the response it evoked. Advocates for redefining "marriage" to include homosexual relationships don't react well to the phrase "biblical marriage". In fact it quickly becomes apparent that there is an angry rebellion against anything "biblical".
But the interesting response I am thinking about just now is the one that makes snide references to David and Solomon et al. who had multiple wives. David is even spoken of by God as the man "after my own heart." This is supposed to prove that biblical marriage can be bigamy and have God's blessing. So what's so problematic about gay marriage?
Such reasoning, of course, comes from a source that is not the least interested in what the bible teaches, unless (of course) that teaching can be shown to be silly or embarrassing. It comes under the category of a little knowledge is a dangerous thing.
Now it doesn't require a Masters degree in logic to understand the point I am about to make. Any fair minded approach to the bible (or any didactic literature) must ask the question, "What is this document trying to say?" That there are examples of multiple wives taken by those who are even heroes of the faith does not prove that this is biblical marriage. It only proves that the bible is honest about the sinful lives of even the best of men. It records such as historical fact.
Rather the question is "What is the kind of marriage that the bible prescribes as ideal and proper." Does the bible say that men should have many wives? When Jesus was accosted by bible teachers who wished to justify divorce, Jesus went back to basics. He said, "Have you not read that He who created them from the beginning made them male and female, and said, 'Therefore a man shall leave his father and his mother and hold fast to his wife, and they shall become one flesh.'?" (Mat. 19:4-5)
Whatever one reads in the bible, he should ask himself, "Is this a normative text?" That is to say, is this what the bible is telling me how I should conduct my life? Or is it another instance of recording the hard truth about people?
In any case, dear reader, you must realize that the bible is at heart a message of the love and grace of God. It tells us how God is very holy, and we are not. If we are desirous of living in God's presence in heaven, our sinful record needs to be erased and our sinful hearts need to be changed. Jesus, God's one and only Son, can make those changes, but he will only do it for those who recognize their sin and ask Him for salvation.
Please don't ever make the mistake of thinking the bible presents us with some sort of moralistic ladder by which we climb our way to heaven. There are high moral standards presented for sure. These are intended to make us realize we are sinful and cannot save ourselves. These moral teachings are also there to help those who already have been forgiven and changed to understand what kind of living pleases God. One of the sure signs that one's heart has been changed is that he now wants to keep God's commandments, especially to love God and others.
And only one of those moral standards is that marriage is a lifetime relationship between one man and one woman.