Genesis 49:3

Jacob used the term "firstborn" in this general sense of dignified excellence when blessing his unworthy eldest son, Reuben: "Reuben, you are my firstborn, my might, and the firstfruits of my strength, preeminent in dignity and preeminent in power" (Gen. 49:3). That is the rank the title of "firstborn" gave Reuben over his brothers. But in his case its value to him and his descendants was largely lost through his own sinful failure.

This is what he was as the firstborn. In himself he was "unstable as water," and he should not excel. Gen. 49:3-4. He forfeited his birthright for defiling his father's bed. It was given to Joseph, who in Ephraim and Manasseh had a double portion among the tribes. 1 Chr. 5:1. The law declared that if a man's firstborn son was by a wife he hated, he must not put another wife's son in his place. The firstborn must have a double portion of all that the man owned, "for he is the firstfruits of his strength. The right of the firstborn is his." Deut. 21:16-17. … Esau is called a profane person for selling his birthright. It was a privilege God had given him, and he should have valued it as such. Gen. 25:31-34; Heb. 12:16.

Reuben was the firstborn. In him above all, the might, the strength, the dignity and the power of Jacob should show. The very beginning of Jacob's strength and excellency were to appear in him. And what appeared? Nothing but instability and self-gratification — defiling, an outrage on all natural decency. What a disappointment for Jacob, to see this evil come out as the beginning of his strength!

Reuben stands for the dignity of nature — not the flesh, for God does not bless the flesh. He stands for man as natural: fallen now, yes, but not fallen of necessity. Man's nobility lies in his intelligent will, and only such a will truly deserves the name. Without it he would be a mere machine worked by other hands, or a boat adrift with no oar or rudder. … Sin has come in, and his will has become self-will — an independent energy stamped with "vanity." That is a "bubbling over," which is what the word "unstable," used here of Reuben, really means. … So the will in man has lost its dignity, and become his degradation.

The firstborn are pictures of human excellence. They are the sons with a natural claim to the birthright, the place of honour and rule. … "Reuben," says the dying father, "you are my firstborn … preeminent in dignity and preeminent in power." But he had to add, "Unstable as water, you shall not have preeminence." So the firstborn sons in the book of Genesis lose the place of blessing. Cain, what is he? Ishmael gives place to Isaac; Esau to Jacob; Reuben to Joseph. "That which is first is natural, and afterwards that which is spiritual."

The fallen, unstable first man must give place to the Second Man. He is the only One who could stand before God. And He stands for the feeblest of those who put their trust in Him.

It is a complete historical prophecy. In it we see, as in a mirror, God's account of men, shown in the twelve tribes. The great lesson in it is the setting aside of the responsible man (the first man), and the bringing in of Christ. All true blessing, whether heavenly or earthly, must come through the second Man.