Genesis 2:21

And the LORD God caused a deep sleep to fall upon Adam, and he slept: and he took one of his ribs, and closed up the flesh instead thereof;

And the Lord God caused a deep sleep to fall upon Adam, [Hebrew, tardeemaah (H8639), a state of sleep more profound than usual, amounting, as is probable, to an almost entire suspension of the functions proper to the nervous system]. How long Adam was left to brood over disappointed hopes we are not informed. But it must have been a short time only, since himself was created, and the whole work of creation finished, before the close of the sixth day. It was probably while his mind was still lingering on the memory of the foregoing scene that he fell into a profound slumber; and since dreams for the most part pursue the course of the thoughts in our waking hours, is it surprising if the first man, whose mental constitution was the same as ours, should have had still flitting before his roving fancy the ideal image of a transaction which must have powerfully excited his interest, and stirred the depths of his reflection? But the sleep by which he was overtaken was not a natural one, nor the visions of his fancy the usual vagaries of a dream.

The word used to describe it is a strongly expressive one (cf. Genesis 15:12; 1 Samuel 26:12), denoting a sleep in which visions occur. 'The Septuagint has translated it, as occurring on such occasions, by ekstasis (G1611), or trance, in which the mind is, as it were, removed from the body, or at least placed beyond the consciousness of any immediate influence of the corporeal world. In such a state it is so completely absorbed with the images impressed upon the imagination, that it not only regards them as realities, but conducts itself toward them as actual matters of fact' (Henderson 'On Inspiration'). (Compare Acts 10:10; Acts 22:17.) This is the meaning of the term employed to describe the condition into which Adam was thrown preparatory to the creation of Eve, during which his senses were so completely locked up that he had no susceptibility of pain from the operation; and such being the import of the word, there can be no difficulty in admitting the account which Josephus and other Jewish writers give, on the authority of ancient traditions, that the whole scene of the formation of Eve was visible to the mental eye of Adam; and hence, the origin of his rapturous exclamation, when the dissolution of the supernatural trance had unsealed his lips - "This is now bone of my bones and flesh of my flesh."

And he took one of his ribs, [Hebrew, tselaa` (H6763), a rib, more frequently the side, and accordingly, the Septuagint version renders it by pleura (G4125), a piece of his side].