William Burkitt on Matthew 19:4

Observe here, Christ gives no direct answer to the Pharisees insnaring question, but refers them to the first institution of marriage, when God made them one, to the intent that matrimonial love might be both incommunicable and indissoluble.

Whence learn, 1. The sacred institution of marriage: it is an ordinace of God's own appointment, as the ground and foundation of all sacred and civil society. What God has joined together.

Learn, 2. The antiquity of this institution, it was from the beginning: He which made them at the beginning, made them male and female. Marriage is almost as old as the world, as old a nature; there was no sooner one person, but God divided him into two; and no sooner were there two, but he united them into one.

Learn hence, 3. The intimacy and nearness of this endeared and endearing relation: the conjugal knot is tied so close, that the bonds of matrimonial love are stronger than those of nature: stricter is the tie betwixt husband and wife, than betwixt parent and children, according to God's own institution. For this cause shall a man leave father and mother, and cleave to his wife.