Matthew 22:34-40 (RSV)

34: But when the Pharisees heard that he had silenced the Sad'ducees, they came together.
35: And one of them, a lawyer, asked him a question, to test him.
36: "Teacher, which is the great commandment in the law?"
37: And he said to him, "You shall love the Lord your God with all your heart, and with all your soul, and with all your mind.
38: This is the great and first commandment.
39: And a second is like it, You shall love your neighbor as yourself.
40: On these two commandments depend all the law and the prophets."