The commandments are the orders that God gives us so that we can be happy,by finding him and finding salvation. What is the commandment that supports all the others? What is necessary to be able to fulfill the rest of the commandments?
An unfriendly lawyer asks the question “Which is the greatest commandment in the law?
The Old Testament has 613 commandments, and there is no clear standard for judging which is greatest. In one sense, because God gave the commandments, all are of equal importance. However, rabbis speak of some commandments as “heavy” and others as “light”.
Jesus said to him “You shall love the Lord your God with all your heart, with all your soul, and with all your mind”. This is from Deuteronomy 6:4-5. These are the words of the Shema, that are recited in daily worship, which are truly engraved on Jewish hearts. The Shema says to love God with heart, soul, and might, but Jesus says heart, soul and mind.
Jesus could stop now, because he is standing on safe ground, but he continues, “A second likewise is this, ‘You shall love your neighbor as yourself’”. This comes from Leviticus 19:18. When Jesus says that the second commandment is like the first, he means that they are related and have similar weight. Love of God naturally leads to love of neighbor, and love of neighbor is part of loving God.
“The whole law and the prophets depend on these two commandments” These two commandments summarize the greatest wisdom to be found in scripture. Torah law (Genesis through Deuteronomy) is the most precious part of Hebrew scripture, and the prophets (Isaiah through Malachi) are next most important.