It is the purpose of this study to show that a child (the natural outcome of the physical union of male and female) is the real meaning of the term "one flesh" used in a biblical context. Not as is usually implied, the mystical "joining" of two beings through ritual or ceremony. It is not the intention of this study, but if we were to embark on a careful examination of the importance and place of "seed" or offspring in the "biblical society" I believe we will throw further light on this proposition.
In Genesis we read, "For this reason a man will leave his father and mother and be united to his wife, and they will become one flesh". Gen 2:24. This verse follows the creation of the second human being, the "helpmeet" or "complement" to the male being. In the context of creation and the later commandment to "multiply" we may propose the idea of "one flesh" to refer to the wonderfully creative and genetically accurate fulfilment of that human "union" in a child created in "the likeness and image" of the parents.
"When Adam had lived 130 years, he had a son in his own likeness, in his own image; and he named him Seth." Gen 5:3. Rather than the traditional mystical "union" attributed to marriage. How often do we hear "isn't he/she like (this or that) parent/relative". How many of us hear our parent's voice in our own speech or manner? Few would argue that most of us are a composite of our parents with the naturally resulting "mix" of certain traits creating a new person, a new individuality.
In these days of contraception, and planned families it is easy to loose sight of the more obvious divine intention and the responsibilities and consequences of sexual union.
Jesus said quoting Genesis 2:24 "'For this reason a man will leave his father and mother and be united to his wife, and the two will become one flesh'" Mat 19:5, (Mar.10:8).
Jesus is speaking in support of the permanence of marriage, while the Pharisees where seeking to justify divorce as allowed by Moses. Jesus is taking opportunity to "underline" human sinfulness, especially to the Pharisees who considered themselves more righteous than their fellows and at the same time explain the provision and grace of God.
The whole of the "Law" was given because of the "hardness" of human hearts. Both the Pharisees and Jesus agreed that the commands to "Love.... God.... and.... neighbours as yourself" summed up the whole law. The rest was only given as "commentary" because of the "hardness" of our hearts.
36 "Teacher, which is the greatest commandment in the Law?" 37 Jesus replied: "'Love the Lord your God with all your heart and with all your soul and with all your mind.' [Deut. 6:5] 38 This is the first and greatest commandment. 39 And the second is like it: 'Love your neighbour as yourself.' [Lev. 19:18] 40. All the Law and the Prophets hang on these two commandments." Mat 22:36-40
Clearly stated here are the words "they are no longer two, but one". A "contract" has been made between two persons by an act ordained by the creator and the resulting "union" is intended to be permanent. However, it is also clear that the "union" can be terminated under certain conditions and with stipulated restrictions, even if not God's original intention.
This indeed emphasizes the "contractual" nature of the union rather than the "spiritual" or "mystical" one. It does not lessen the gravity of the act but helps us see marriage in the practical perspective intended by God. This does not belittle or lessen the importance of marriage. Covenants or contracts are "heavy stuff" with God. We need to know what they are about and the obligations involved. As is sometimes said in the marriage service - it/they "should not be entered into lightly".
As so often in other matters the traditional emphasis we have "majored on the minors". Weaving a pretty, mystical fabric around marriage, while neglecting the basis principles and the resulting consequences of our neglect. A good example of this is the modern attitude of major "Christian" denominations towards homosexuality and bigamy. Clergy make compromising statements on homosexuality while condemning bigamy while the Bible condemns homosexuality but says little on bigamy.
Many talk about "sex outside marriage. In Catholic tradition a marriage, correctly, has not actually taken place, until "consummated". This suggests that the basic unbreakable commitment between a male and female is actually made in bed. However, even among Catholics, the idea of "one flesh" still seems to pertain to the mystical rather than the practical. Most other denominations have lost the connection altogether making marriage some sort of (more or less) mystical ritual that is consummated by a "celebrant" saying "I pronounce you man and wife".
"Do you not know that he who unites himself with a prostitute is one with her in body? For it is said, "The two will become one flesh."" (Gen. 2:24) 1Cor 6:16
With this statement Paul give a clear indication of how he at least understood Genesis 2:24 and if we realise how important "descendants", "hereditary" and "inheritance" are in the scriptures we will see that there is a very practical meaning and purpose in the idea of "one flesh". The idea of doubtful parentage would play havoc with the hereditary structure of the nation of families founded and rooted in the 12 patriarchs. God gave Moses laws of inheritance that depended on clear genealogical lines being established and respected. To become "one flesh" with someone not wholly committed to the structure could and did cause all kinds of problems.