It is greatest, because, in a sense, it includes all the other laws. Polytheism, atheism, idolatry, and all sins against God are forbidden by it. Where we love, we desire to bless. There is none other commandment greater than these. On these two commandments the whole law hangeth, and the prophets.
Love begets a desire to bless, but the law guides to the accomplishment of that desire.
Perfect righteousness is the result of wisdom as well as affection. Thou art not far from the kingdom of God.