My son, forget not my law,.... Or, "doctrine" (e); the doctrine of Christ, the Gospel, and the several truths of it; which, being of the utmost moment and importance, should be kept in memory, and not let slip, or be in the least slighted and neglected; see Heb 2:1; but let thine heart keep my commandments; as the ark, or chest, kept the two tables of the law put into it; it denotes a cordial affection for the commandments and ordinances of Christ, a hearty attention and obedience to them, and a constant and cheerful observance of them, flowing from love and gratitude to him, Joh 14:15. (e) "doctrinae meae", Piscator, Michaelis; "institutionem meam", Schultens; "doctrinam meam", Cocceius.