Deuteronomy 6:5

Thou shalt love the Lord, etc. - Here we see the truth of that word of the apostle, 1 Timothy 1:5 : Now the End of the Commandment is Love out of a pure heart, etc. See the whole of the doctrine contained in this verse explained on Matthew 22:36-40 (note).

Since there is but One God, and that God is Israel's God, so Israel must love God unreservedly and entirely. The "heart" is mentioned as the seat of the understanding; the "soul" as the center of will and personality; the "might" as representing the outgoings and energies of all the vital powers.

The New Testament itself requires no more than this total self-surrender of man's being to his maker Matthew 22:37. The Gospel differs from the Law not so much in replacing an external and carnal service of God by an inward and spiritual one, as in supplying new motives and special assistances for the attainment of that divine love which was, from the first and all along, enjoined as "the first and great commandment."

6:5 And thou shalt love the Lord thy God with all thine heart - And is this only an external commandment? Can any then say, that the Sinai - covenant was merely external? With all thy heart - With an entire love. He is One; therefore our hearts must be united in his love. And the whole stream of our affections must run toward Him.O that this love of God may be shed abroad in our hearts.