Hebrews 6:13-15 - Joseph Benson’s Commentary on the Old and New Testaments

For when God made promise, &c. As if he had said, And it appears that this is the way to partake of mercies promised, because Abraham was obliged to exercise faith and long-suffering before he obtained the accomplishment of the promise made to him. The promise here referred to, is that which God made to Abraham after he had laid Isaac on the altar, Genesis 22:16-17. For on no other occasion did God confirm any promise to Abraham with an oath. To Abraham Whose spiritual as well as natural seed you believing Hebrews are, and therefore shall partake of the same promises and blessings which were ensured to him. Because he could swear by no greater person, he sware by himself By his own sacred and divine name; saying, Surely blessing I will bless thee And all believers in thee; and multiplying I will multiply thee Both thy natural and thy spiritual seed. The apostle quotes only the first words of the oath; but his reasoning is founded on the whole; and particularly on the promise, (Genesis 22:18,) And in thy seed all the nations of the earth shall be blessed. They shall be blessed by having their faith counted to them for righteousness, through thy seed, Christ. And so after he had patiently endured Μακροθυμησας, after he had waited, or suffered long: he waited about thirty years before Isaac was born, after he was promised; he obtained the promise Here, by a usual figure of speech, the promise is put for the thing promised. “In the birth of Isaac, Abraham obtained the beginning of the accomplishment of God's promise concerning his numerous natural progeny. Moreover, as the birth of Isaac was brought about supernaturally by the divine power, it was both a proof and a pledge of the accomplishment of the promise concerning the birth of his numerous spiritual seed. Wherefore, in the birth of Isaac, Abraham may truly be said to have obtained the accomplishment of the promise concerning his numerous spiritual seed likewise. In any other sense, Abraham did not obtain the accomplishment of that promise.”