28 Then one of the scribes [an expert in Mosaic Law] came up and listened to them arguing [with one another], and noticing that Jesus answered them well, asked Him, “Which commandment is first and most important of all?” 29 Jesus answered, “The first and most important one is: ‘Hear, O Israel, the Lord our God is one Lord; 30 and you shall love the Lord your God with all your heart, and with all your soul(life), and with all your mind (thought, understanding), and with all your strength.’
Mark 12:28-30 (AMP)