(20) He is thy life, and the length of thy days.--This is the Old Testament form of a well-known saying in the New Testament, which may yet be fulfilled in Israel, "I am the resurrection and the life. He that believeth in me, though he were dead, yet shall he live; and whosoever liveth and believeth in me shall never die" (John 11:25-26).

Verse 20. - For he is thy life; rather, for this is thy life; to love the Lord is really to live the true, the higher life (cf. Deuteronomy 4:40; Deuteronomy 32:47).

30:15-20 What could be said more moving, and more likely to make deep and lasting impressions? Every man wishes to obtain life and good, and to escape death and evil; he desires happiness, and dreads misery. So great is the compassion of the Lord, that he has favoured men, by his word, with such a knowledge of good and evil as will make them for ever happy, if it be not their own fault. Let us hear the sum of the whole matter. If they and theirs would love God, and serve him, they should live and be happy. If they or theirs should turn from God, desert his service, and worship other gods, that would certainly be their ruin. There never was, since the fall of man, more than one way to heaven; which is marked out in both Testaments, though not with equal clearness. Moses meant that same way of acceptance, which Paul more plainly described; and Paul's words mean the same obedience, on which Moses more fully treated. In both Testaments the good and right way is brought near, and plainly revealed to us.That thou mayest love the Lord thy God,.... And show it by keeping his commands:

and that thou mayest obey his voice; in his word, and by his prophets:

and that thou mayest cleave unto him; and to his worship, and not follow after and serve other gods:

for he is thy life, and the length of thy days; the God of their lives, and the Father of their mercies; the giver of long life, and all the blessings of it; and which he had promised to those that were obedient, to him, and which they might expect:

that thou mayest dwell in the land which the Lord sware unto thy fathers, to Abraham, to Isaac, and to Jacob, to give them; the land of Canaan, often thus described; this was the grand promise made to obedience to the law, and was typical of eternal life and happiness; which is had, not through man's obedience to the law, but through the obedience and righteousness of Christ.