The great commandment
Deutoronomy 6:4-9 NIV
4 Hear, O Israel: The Lord our God, the Lord is one. 5 Love the Lord your God with all your heart and with all your soul and with all your strength. 6 These commandments that I give you today are to be on your hearts. 7 Impress them on your children. Talk about them when you sit at home and when you walk along the road, when you lie down and when you get up. 8 Tie them as symbols on your hands and bind them on your foreheads. 9 Write them on the doorframes of your houses and on your gates.