John Calvin Commentary Genesis 2:21

"And Jehovah God caused a deep sleep to fall upon the man, and he slept; and he took one of his ribs, and closed up the flesh instead thereof:" — Genesis 2:21 (ASV)

And the Lord God caused a deep sleep to fall, etc. Although to profane persons this method of forming woman may seem ridiculous, and some of these may say that Moses is dealing in fables, yet to us the wonderful providence of God clearly shines here. For, so that the union of the human race might be more sacred, He purposed that both males and females should spring from one and the same origin.

Therefore, He created human nature in the person of Adam, and from him formed Eve, so that the woman would be only a portion of the whole human race. This is the meaning of the words of Moses we encountered earlier (Genesis 1:28): “God created man... he made them male and female.” In this manner, Adam was taught to recognize himself in his wife, as in a mirror; and Eve, in her turn, to submit herself willingly to her husband, as she was taken out of him.

But if the two sexes had proceeded from different sources, there would have been occasion for either mutual contempt, envy, or disputes. And what do perverse men object to here? ‘The narration does not seem credible, since it is contrary to custom.’

As if, indeed, such an objection would be more plausible than one raised against the usual way humankind is produced, if the latter were not known by common experience! But they object that either the rib taken from Adam was superfluous, or that his body was mutilated by the absence of the rib.

To either of these objections, it may be answered that they themselves reveal a great absurdity. If, however, we were to say that the rib from which He would form another body had been previously prepared by the Creator of the world, I find nothing in this answer that is not in accordance with Divine Providence.

Yet I am more in favor of a different conjecture: namely, that something was taken from Adam so that he might embrace a part of himself with greater benevolence. He lost, therefore, one of his ribs; but, instead of it, a far richer reward was granted him, since he obtained a faithful associate for life. For he now saw himself, who had previously been incomplete, made complete in his wife.

And in this, we see a true resemblance of our union with the Son of God, for He became weak that He might have members of His body endowed with strength.

In the meantime, it should be noted that Adam had been plunged into such a deep sleep that he felt no pain. Furthermore, the separation was not violent, nor was any lack of the lost rib perceived, because God so filled up the empty space with flesh that his strength remained unimpaired; only the hardness of bone was removed.

Moses also deliberately used the word built to teach us that in the person of the woman, the human race was at last complete, which had previously been like a building just begun. Others refer the expression to the family order, as if Moses would say that legitimate family structure was then instituted, which does not differ widely from the former interpretation.