Mark 12:33
and to love Him with one's whole heart, one's whole understanding, and one's whole strength, and to love one's neighbor as one loves himself is far more than all the burnt-offerings and sacrifices."
John 16:24
Up to this time you have not asked for anything as bearers of my name, but now you must keep on asking, and you will receive, that your cup of joy may be full to the brim.
John 21:17
For the third time Jesus asked him, "Simon, son of John, do you really tenderly love me?" Peter was hurt because Jesus the third time asked him, "Do you really tenderly love me?" So he answered Him, "Lord, you know everything; you know that I do tenderly love you." Jesus said to him, "Then feed my sheep.
1 John 4:19
We love, because He loved us first.
1 John 5:2-3
This is how we can be sure that we love the children of God, by continuing to love God and to obey His commands.