Hebrews 6:13-18

Verse 13

When God made promise to Abraham - The promise referred to is that made to Abraham when he had offered his son Isaac on the altar, Gen 22:16-18 : "By myself have I sworn, saith the Lord; for because thou hast done this thing, and hast not withheld thy son, thy only son; that in blessing I will bless thee, and in multiplying I will multiply thy seed as the stars of the heaven, and as the sand which is upon the seashore; and thy seed shall possess the gate of his enemies; and in thy seed shall all the nations of the earth be blessed." Of this promise the apostle only quotes a part, as is generally the case, because he knew that his readers were well acquainted with the Scriptures of the Old Testament, and particularly with the law.

He sware by himself - He pledged his eternal power and Godhead for the fulfillment of the promise; there was no being superior to himself to whom he could make appeal, or by whom he could be bound, therefore he appeals to and pledges his immutable truth and Godhead.
Verse 14

Saying, Surely blessing I will bless thee - I will continue to bless thee.

Multiplying I will multiply thee - I will continue to increase thy posterity. In the most literal manner God continues to fulfill this promise; genuine Christians are Abraham's seed, and God is increasing their number daily. See the notes on Gen 22:12-18 (note); and Gen 23:1 (note).
Verse 15

He obtained the promise - Isaac was supernaturally born; and in his birth God began to fulfill the promise: while he lived, he saw a provision made for the multiplication of his seed; and, having continued steadfast in the faith, he received the end of all the promises in the enjoyment of an eternal glory. And the inference from this is: If we believe and prove faithful unto death, we shall also inherit the promises; and this is what is implied in the apostle's exhortation, Heb 6:12 : Be not slothful, but followers of them, etc.
Verse 16

Men verily swear by the greater - One who has greater authority; who can take cognizance of the obligation, and punish the breach of it.

An oath for confirmation - "This observation teaches us," says Dr. Macknight, "that both promissory oaths concerning things lawful and in our power, and oaths for the confirmation of things doubtful, when required by proper authority, and taken religiously, are allowable under the Gospel."
Verse 17

The heirs of promise - All the believing posterity of Abraham, and the nations of the earth or Gentiles in general.

The immutability of his counsel - His unchangeable purpose, to call the Gentiles to salvation by Jesus Christ; to justify every penitent by faith; to accept faith in Christ for justification in place of personal righteousness; and finally to bring every persevering believer, whether Jew or Gentile, to eternal glory.
Verse 18

That by two immutable things - The promise and oath of God: the promise pledged his faithfulness and justice; the oath, all the infinite perfections of his Godhead, for he sware by himself. There is a good saying in Beracoth on Exo 32:13, fol. 32: Remember Abraham, Isaac, and Israel, thy servants, to whom thou swarest by thine own self. "What is the meaning of by thine own self? Rab. Eleazar answered, Thus said Moses to the holy blessed God, Lord of all the world. If thou hadst sworn to them by the heavens and the earth, then I should have said, As the heavens and the earth shall pass away, so may thy oath pass away. But now thou hast sworn unto them by thy great name, which liveth, and which endureth for ever, and for ever and ever; therefore thy oath shall endure for ever, and for ever and ever."

This is a good thought; if God had sworn by any thing finite, that thing might fail, and then the obligation would be at an end, but he has sworn by what is infinite, and cannot fail; therefore his oath is of eternal obligation.

We might have a strong consolation - There appears to be an allusion here to the cities of refuge, and to the persons who fled to them for safety. As the person who killed his neighbor unawares was sure if he gained the city of refuge he should be safe, and had strong consolation in the hope that he should reach it, this hope animated him in his race to the city; he ran, he fled, knowing that, though in danger the most imminent of losing his life, yet, as he was now acting according to an ordinance of God, he was certain of safety provided he got to the place.

It is easy to apply this to the case of a truly penitent sinner. Thou hast sinned against God and against thy own life! The avenger of blood is at thy heels! Jesus hath shed his blood for thee, he is thy intercessor before the throne; flee to him! Lay hold on the hope of eternal life which is offered unto thee in the Gospel! Delay not one moment! Thou art never safe till thou hast redemption in his blood! God invites thee! Jesus spreads his hands to receive thee! God hath sworn that he willeth not the death of a sinner; then he cannot will thy death: take God's oath, take his promise; credit what he bath spoken and sworn! Take encouragement! Believe on the Son of God, and thou shalt not perish, but have everlasting life!
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