Genesis 2:24

24 That is why a man leaves his father and mother and is united to his wife, and they become one flesh.

Read Genesis 2:24 Using Other Translations

Therefore shall a man leave his father and his mother, and shall cleave unto his wife: and they shall be one flesh.
Therefore a man shall leave his father and his mother and hold fast to his wife, and they shall become one flesh.
This explains why a man leaves his father and mother and is joined to his wife, and the two are united into one.

What does Genesis 2:24 mean?

John Gill's Exposition of the Bible
Genesis 2:24

Therefore shall a man leave his father, and his
mother
These are thought by some to be the words of Moses, inferring from the above fact, what ought to be among men; and by others, the words of Adam under divine inspiration, as the father of mankind instructing his sons what to do, and foretelling what would be done in all succeeding ages: though they rather seem to be the words of God himself, by whom marriage was now instituted; and who here gives direction about it, and declares the case and circumstance of man upon it, and how he would and should behave: and thus our Lord Jesus Christ, quoting these words, makes them to be the words of him that made man, male and female, and supplies and prefaces them thus, and said, "for this cause" ( Matthew 19:5 ) so Jarchi paraphrases them,

``the Holy Ghost said so:''
not that a man upon his marriage is to drop his affections to his parents, or be remiss in his obedience to them, honour of them, and esteem for then, or to neglect the care of them, if they stand in need of his assistance; but that he should depart from his father's house, and no more dwell with him, or bed and board in his house; but having taken a wife to himself, should provide an habitation for him and her to dwell together: so all the three Targums interpret it, of quitting "the house of his father, and his mother's bed", and shall cleave unto his wife;
with a cordial affection, taking care of her, nourishing and cherishing her, providing all things comfortable for her, continuing to live with her, and not depart from her as long as they live: the phrase is expressive of the near union by marriage between man and wife; they are, as it were, glued together, and make but one; which is more fully and strongly expressed in the next clause: and they shall be one flesh;
that is, "they two", the man and his wife, as it is supplied and interpreted by Christ, ( Matthew 19:5 ) and so here in the Targum of Jonathan, and in the Septuagint and Samaritan versions: the union between them is so close, as if they were but one person, one soul, one body; and which is to be observed against polygamy, unlawful divorces, and all uncleanness, fornication, and adultery: only one man and one woman, being joined in lawful wedlock, have a right of copulation with each other, in order to produce a legitimate offspring, partaking of the same one flesh, as children do of their parents, without being able to distinguish the flesh of the one from the other, they partake of: and from hence it appears to be a fabulous notion, that Cecrops, the first king of Athens, was the first institutor of matrimony and joiner of one man to one woman; whence he was said to be "biformis" {p}, and was called (difuhv) ; unless, as some F17 have thought, that he and Moses were one and the same who delivered out the first institution of marriage, which is this.
FOOTNOTES:

F16 Justin. e Trogo, l. 2. c. 6.
F17 Vid. Saldeni Otia Theolog. Exercitat. 1. sect. 14. p. 13, 14.
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