Charles Ellicott Commentary Genesis 29:26

"And Laban said, It is not so done in our place, to give the younger before the first-born." — Genesis 29:26 (ASV)

It must not be so done in our country. —Hebrew, It is not so done in our place, to give, etc. We have seen that it is still customary for the elder cousin to take the elder daughter, and the younger the younger. But Laban affirms that if the elder daughter was not claimed, it was the rule in Haran for her to take precedence over her sisters. In India the practice is such as Laban describes, but we have no proof of the existence of any such custom among the Bedouin. Apparently Leah loved Jacob (Genesis 30:15), and Laban wanted a continuation of his service, and so this unscrupulous plot was arranged between them on a pretext which, if not false, was yet overstrained. Jacob plainly had no idea of such a custom and would not have given seven years’ service for Leah.