The Design and Purpose of Marriage
In Genesis chapter two, history records God's words regarding the partnership of men and women. "And the LORD God said, 'It is not good that man should be alone; I will make him a helper comparable to him'" (vs. 18). In commenting on that partnership, the inspired writer records, "Therefore a man shall leave his father and mother and be joined to his wife, and they shall become one flesh" (vs. 24). Jesus, commenting on this passage of scripture, said, "So then, they are no longer two but one flesh. Therefore what God has joined together, let not man separate" (Matthew 19:6).
These passages describe the divine origin of the marriage relationship, and express its sensible design. Despite man's attempts over the years to modify the parameters of the marriage relationship, the principle established by scripture of one man for one woman for a lifetime will remain the foundation of humankind's existence. Assaults upon the foundation of the home invariably have a deleterious effect upon societies, and have even contributed to the decline and fall of nations.
It is important for us to know the purpose and design of the marriage relationship, to keep this institution strong. A strong home leads to a strong nation, and more importantly, a strong church.
The Purpose of Marriage
Simply put, the marriage relationship affords a stable environment in which to raise children. Now, this does not invalidate childless homes, but it does recognize that God designed the husband/wife relationship to be the building block of society. "So God created man in His own image; in the image of God He created him; male and female He created them. Then God blessed them, and God said to them, "Be fruitful and multiply; fill the earth and subdue it; have dominion over the fish of the sea, over the birds of the air, and over every living thing that moves on the earth" (Genesis 1:27-28). The husband/wife relationship is the most intimate in life, and in it alone is sexual activity appropriate and acceptable. "Marriage is honorable among all, and the bed undefiled; but fornicators and adulterers God will judge" (Hebrews 13:4).
The Design of Marriage
As the primary purpose of the marriage relationship is to "be fruitful and multiply", the relationship must be defined in sexual terms. Again, this does not mean that sexual activity is the only important thing between a husband and wife; much to the contrary; but it does indicate that in marriage alone is sexual activity acceptable (see Heb. 13:4 above).
Three things become immediately apparent as we recognize the sexual aspects of the marriage relationship. First, that marriage, by definition, is a relationship between a man and a woman. Setting aside the condemnation of homosexuality which is so common to scripture (cf. Romans 1:28-32), the purpose of the home is to procreate. This is impossible in a homosexual marriage, and is unnatural. Men may seek to change marriage, but God from the beginning said, "a man shall leave his father and mother and be joined to his wife, and the two shall become one flesh" (cf. Genesis 2:24).
Second, the obligation of sexual activity is found in the marriage relationship. So often the emphasis is placed upon the prohibition of sex outside of marriage, that there is a neglect in teaching the obligation of the individual within the marriage relationship. Paul did not neglect to teach on this delicate subject, and said in 1 Corinthians 7:2-5, "Nevertheless, because of sexual immorality, let each man have his own wife, and let each woman have her own husband. Let the husband render to his wife the affection due her, and likewise also the wife to her husband. The wife does not have authority over her own body, but the husband does. And likewise the husband does not have authority over his own body, but the wife does. Do not deprive one another except with consent for a time, that you may give yourselves to fasting and prayer; and come together again so that Satan does not tempt you because of your lack of self-control." The sexual drive is so strong that specific instruction is given by the apostle to the obligation, (before God), which each spouse has to the other.
Third, sexual immorality is a horrible sin, and sufficient to destroy the marriage bond. Paul said, "Flee sexual immorality. Every sin that a man does is outside the body, but he who commits sexual immorality sins against his own body" (1 Corinthians 6:18).
Jesus indicated that sexual immorality, (i.e. fornication), is the sole scriptural cause for an individual to divorce his or her spouse. "And I say to you, whoever divorces his wife, except for sexual immorality, and marries another, commits adultery; and whoever marries her who is divorced commits adultery" (Matthew 19:9). Sexual immorality is so destructive to the marriage bond that Jesus allows the dissolution of the bond in such cases. Any other "cause", coupled with remarriage, is unacceptable to Him.
While the husband/wife relationship is not exclusively defined by its sexual aspect, that is what makes it unique. Sex is a blessed privilege and obligation in that union, but is unacceptable in any other context. Men have largely rejected these facts, but the future welfare of our society is dependent upon our acceptance of this truth.