Mark 12:28-30

Then one of the scribes came, and having heard them reasoning together, perceiving that He had answered them well, asked Him, “Which is the first commandment of all?” Jesus answered him, “The first of all the commandments is: ‘Hear, O Israel, the LORD our God, the LORD is one. And you shall love the LORD your God with all your heart, with all your soul, with all your mind, and with all your strength.’ This is the first commandment.