Deuteronomy 6:5: Deu 6:5
As the one God, therefore, Israel was to love Jehovah its God with all its heart, with all its soul, and with all its strength. The motive for this is to be found in the words “thy God,” in the fact that Jehovah was Israel’s God, and had manifested Himself to it as one God. The demand “with all the heart” excludes all half-heartedness, all division of the heart in its love. The heart is mentioned first, as the seat of the emotions generally and of love in particular; then follows the soul (nephesh) as the centre of personality in man, to depict the love as pervading the entire self-consciousness; and to this is added, “with all the strength,” sc., of body and soul. Loving the Lord with all the heart and soul and strength is placed at the head, as the spiritual principle from which the observance of the commandments was to flow (see also Deu 11:1; Deu 30:6). It was in love that the fear of the Lord (Deu 10:12), hearkening to His commandments (Deu 11:13), and the observance of the whole law (Deu 11:22), were to be manifested; but love itself was to be shown by walking in all the ways of the Lord (Deu 11:22; Deu 19:9; Deu 30:16). Christ therefore calls the command to love God with all the heart “the first and great commandment,” and places on a par with this the commandment contained in Lev 19:8 to love one’s neighbour as oneself, and then observes that on these two commandments hang all the law and the prophets (Mat 22:37-40; Mar 12:29-31; Luk 10:27).
Even the gospel knows no higher commandment than this. The distinction between the new covenant and the old consists simply in this, that the love of God which the gospel demands of its professors, is more intensive and cordial than that which the law of Moses demanded of the Israelites, according to the gradual unfolding of the love of God Himself, which was displayed in a much grander and more glorious form in the gift of His only begotten Son for our redemption, than in the redemption of Israel out of the bondage of Egypt.