103:15-18 How short is man's life, and uncertain! The flower of the garden is commonly more choice, and will last the longer, for being sheltered by the garden-wall, and the gardener's care; but the flower of the field, to which life is here compared, is not only withering in itself, but exposed to the cold blasts, and liable to be cropt and trod on by the beasts of the field. Such is man. God considers this, and pities him; let him consider it himself. God's mercy is better than life, for it will outlive it. His righteousness, the truth of his promise, shall be unto children's children, who tread in the footsteps of their forefathers' piety. Then shall mercy be preserved to them.To such as keep his covenant - To such as adhere to the arrangements of his covenant, or who are faithful on their part. God will be faithful to his part of the covenant; and where there is fidelity on the part of his people, the blessings implied in the covenant will be conferred on them and on their children. The promise is ample, and the fidelity of God is certain, but still it is true that in those promises, and in that fidelity, it is implied that his people on their part must be faithful also, or the blessings will not be bestowed. There are no promises of blessings to the unfaithful, nor have those who are unfaithful any reason to hope that they or theirs will be partakers of the blessings of the covenant of mercy. Our only hope that we or our children will be partakers of the blessings of the covenant is to be found in the fact that we ourselves are faithful to God.

And to those that remember his commandments to do them - Who do not "forget" his law. If they do forget it, they have no right to expect the blessing. Obedience and fidelity are our only reasonable grounds of expectation of the blessing of God.

18. such … covenant—limits the general terms preceding.

righteousness—as usual (Ps 7:17; 31:1).

To such as keep his covenant; to them that perform the condition of God’s covenant, that sincerely love and obey him. Such restrictions are oft added, as in the general to overthrow the presumptuous hopes of ungodly men, so particularly to admonish the Israelites not to rest too much upon the privileges of their parents, or the covenant made with them, nor to expect any benefit by it, but upon condition of their continuance in God’s covenant.

That remember his commandments to do them; that have them much in their thoughts, and practise them in the course of their lives.

To such as keep his covenant,.... The covenant of grace, which is peculiarly the Lord's covenant, as distinct from man's; and which he keeps himself, and is ever mindful of it. This he makes known to his people at conversion; his secret is with them, and he shows them his covenant; the blessings and promises of it; their interest in them, and in himself, as their covenant God: which they "observe" (c), as the word here used signifies; and observing it, they lay hold upon it by faith, as belonging to them; and laying hold upon it, they "keep" it as their own, and keep it fast, and will not part with their interest in it for all the world.

And to those that remember his commandments to do them; some read them and hear them, but forget them, at least to do them: these are like a man that beholds his face in a glass, and forgets what manner of man he is; so James compares one that is a forgetful hearer, and not a doer of the word, James 1:23. The commandments of God are best remembered, so as to be done, when he puts his laws into the minds of men, and writes them in their hearts, and puts his Spirit within them, to cause them to walk in his statutes, and do them, Jeremiah 31:34.

(c) "observantes", Junius & Tremellius; so Piscator, Gejerus.

To such as keep his {l} covenant, and to those that remember his commandments to do them.

(l) To whom he gives grace to fear him, and to obey his word.