And Jacob did so - and he gave him Rachel - It is perfectly plain that Jacob did not serve seven years more before he got Rachel to wife; but having spent a week with Leah, and in keeping the marriage feast, he then got Rachel, and served afterwards seven years for her. Connections of this kind are now called incestuous; but it appears they were allowable in those ancient times. In taking both sisters, it does not appear that any blame attached to Jacob, though in consequence of it he was vexed by their jealousies. It was probably because of this that the law was made, Thou shalt not take a wife to her sister, to vex her, besides the other in her life-time. After this, all such marriages were strictly forbidden.

And Jacob did so, and fulfilled her week,.... The week of the days of the feast of Leah, as the Targum of Jonathan adds; he agreed to it; during which time he cohabited with Leah as his wife, and which confirmed the marriage: how justifiable this was, must be left. The marrying of two sisters was forbidden by the law of Moses, Leviticus 18:18; and polygamy was not allowed of in later times, and yet both were dispensed with in times preceding; and there seems to be an overruling Providence in this affair, which oftentimes brings good out of evil, since the Messiah was to spring from Leah, and not Rachel; See Gill on Genesis 29:35; and having more wives than one, and concubines also, seems to be permitted for this reason, that Jacob might have a numerous progeny, as it was promised he should: and indeed Jacob was under some necessity of marrying both sisters, since the one was ignorantly defiled by him, and the other was his wife by espousal and contract; and though he had served seven years for her, he could not have her without consenting to marry the other, and fulfilling her week, and serving seven years more; to such hard terms was he obliged by an unkind uncle, in a strange country, and destitute:
and he gave him Rachel his daughter to wife also; not after seven years' service, as Josephus (u) thinks, but after the seven days of feasting for Leah; though on condition of the above service, as appears from various circumstances related before the seven years' service could be completed; as his going in to Rachel, Genesis 29:30; her envying the fruitfulness of her sister, Genesis 30:1; giving Bilhah her handmaid unto him, Genesis 30:3; and the whole series of the context, and life of Jacob.
(u) Antiqu. l. 1. c. 19. sect. 7.

gave him Rachel also--It is evident that the marriage of both sisters took place nearly about the same time, and that such a connection was then allowed, though afterwards prohibited (Leviticus 18:18).