Though I have referred to the preface of the Decalogue several times already in this series of posts, it is this Command in particular that demonstrates its relevance to all ten Commands in a way that needs little explanation. I have previously asserted and reasserted that God’s covenantal right over His people is the basis for all the Commands of the Decalogue. The 7th Command brings this home with peculiar force. Among all the possible acts (in word, thought and deed) which this Command expressly treats, the sanctity and purity of marriage is truly at its heart.
This is no surprise because God actually designed marriage as a type of His covenant relationship with His people. Edmund Clowney writes, “In Genesis the command (leave father and mother and be united to his wife - AKU) follows the statement of Adam (‘bone of my bones and flesh of my flesh’). God’s command is grounded in His act of creation. The relation of man and wife is exclusive. The love that’s join them is necessarily a jealous love; that is, it is a focused love that would be broken by adultery. This principle is again stated in the Ten Commandments, when God gives His covenant law to His redeemed people. That commandment, ‘Thou shalt not commit adultery,’ is not given simply to provide a stable home life for Israelite society. It is given to define a special and intensive love that goes beyond the command to love one’s neighbor.
“This is the principle that God himself invokes as He reveals Himself to Israel. God is a jealous; His name is ‘Jealous’ (Ex.34:14). He demands of Israel exclusive devotion, the jealous love for which marriage is a type and symbol. His people are to love Him with all their heart, soul, strength, and mind.” Edmund Clowney, The Unfolding Mystery, pg. 25
The biblical prohibition of divorce lies at the heart of this issue as well. God is bound to His people by covenant. Marriage was meant to illustrate the permanence of God’s covenant love to His people. It can’t very well do that by an institution that can be impulsively severed at will. I am not going to go into a treatment of the supposed biblical exemptions or exceptions for divorce and remarriage except to say that none of the modern arguments were known or accepted by the Christian Church for nearly 1600 years. And no matter how widely we define the "Biblical exception" for divorce, the question remains whether we are supposed to automatically assume that this also automatically allows for remarriage and, we must therefore acknowledge that millions of professing Christians have, in fact, violated Christ's express teaching found in Matthew 5, Matthew 19 and Mark 10.
Our society is awash in open violations of this Command. The ugly list of Leviticus 18 could be the plot-line for a whole series of Jerry Springer episodes. The sexual sins of Sodom, Gomorrah and the Canaanites, for which God destroyed them are rampant in Western society. Premarital sex is almost a meaningless expression because it isn’t even really premarital if the ones engaged in such sin never even get married! Unwed cohabitation is almost a societal norm. Unfortunately this sin is openly engaged in by many professing Christians. Extramarital sex is also hugely rampant both inside and outside of the Church. I remember someone making a joke about what must be in the drinking fountain water in a small church in southern Illinois because they had had more than one pastor run off with the organist or secretary. Extramarital sex is even more rampant in the form of pornography, which despite the modern ease of access, is not new.
Christians have always understood this Command to be referring to more than just adultery, which is defined as sexual relations between two people, at least one of whom is married. The Heidelberg Catechism, picking up on this fact states, “Since both our body and soul are temples of the Holy Ghost, he commands us to preserve them pure and holy: therefore he forbids all unchaste actions, gestures, words, thoughts, desires, and whatever can entice men thereto.”
Besides the obvious sins prohibited by this Command, the underlying principle also applies to general looseness of life and conduct. Such behavior, which used to be called ‘wantonness,’ serves as an occasion of stirring up lust. This would include the ‘wandering eye,’ watching pornography, movies and or TV programs that condone sexual promiscuity, immodest clothing, double entendres or sexual humor, idleness (2 Samuel 11:1-5). By engaging in such things, we desensitize our souls toward things which God hates, and lessen the effects of conviction and conscience in ourselves.
As with the prohibition of murder in the 6th Command, the New Testament emphasizes the internal character of this sin as well. Christ’s famous words in Matthew 5:27-30 stand as an eternal witness that God has always sought internal conformity to His will, not just external compliance.
None of this is new to us, I’m sure; which is why I would rather focus on the point made above in the quote from Clowney. Marriage was created by God to be a picture of Christ and the Church. This is the exact point Paul drives home with great force in Ephesians 5. We should bear it in mind that any violation of the sanctity of marriage is, ipso facto, a repudiation of God’s covenant with His people.
As an aside, a great violation of the principle of this Command as it relates to the relation of God and His people is to be found in unfaithfulness to God’s Word, whether it be in the form of doctrinal infidelity, religious syncretism, unbiblical ecumenical alliances. I do not say this to belittle any reference the Command undoubtedly has to physical marital fidelity, but as per Paul in Ephesians 5, we must remember that marriage is a picture of God’s covenant with His elect. He takes doctrinal infidelity as seriously, if not more, than we would take marital infidelity if we were the victim of it.