St Mark 12:28-31

And there came one of the scribes that had heard them reasoning together, and seeing that he had answered them well, asked him which was the first commandment of all. And Jesus answered him: The first commandment of all is, Hear, O Israel: the Lord thy God is one God. And thou shalt love the Lord thy God, with thy whole heart, and with thy whole soul, and with thy whole mind, and with thy whole strength. This is the first commandment. And the second is like to it: Thou shalt love thy neighbour as thyself. There is no other commandment greater than these.