Matt22:37&39..."LOVE the Lord your God with all your heart and with all your soul and with all your mind...And the second is like it: 'Love your neighbor as yourself'.
The scribes had been debating which of the laws of Moses was the greatest, they were able to document 613 commandments&all you need to break is just one to be guilty of all before God(James2:10). A pharisee asked Jesus which is the greatest in the law of Moses.
Jesus answered his question by giving them the LAW OF LOVE( towards God and our neighbour). To love God is simply to obey Him (1Jhn5:3), it is not the kind of feelings you have for the opposite sex neither is it a lip service you express during worship.
Your joyful obedience is the proof of your Love for God.
HolySpirit, help me to obey God's word joyfully In Jesus Name.