Adam Clarke on Genesis 24:36

Unto him hath he given all that he hath - He has made Isaac his sole heir. These things appear to be spoken to show the relatives of Rebekah that his master's son was a proper match for her; for even in those primitive times there was regard had to the suitableness of station and rank in life, as well as of education, in order to render a match comfortable. Persons of dissimilar habits, as well as of dissimilar religious principles, are never likely to be very happy in a married life. Even the poor and the rich may better meet together in matrimonial alliances than the religious and the profane, the well-bred and the vulgar. A person may be unequally yoked in a great variety of ways: Bear ye one another's burdens is the command of God; but where there is unsuitableness in the dispositions, education, mental capacity, etc., of the persons, then one side is obliged to bear the whole burden, and endless dissatisfaction is the result. See at the end, Gen 24:67 (note).