Love is part of who God is
First John does not simply say that God loves. It says that God is love (1 John 4:8). Love flows from his nature. This does not make God a vague feeling or mean that every desire is loving. It means his actions toward his creation are consistent with his good, holy, generous character.
John also connects knowing God with learning to love. That is not a claim that people earn God's welcome by being nice. Rather, those who come to know him begin to reflect the family likeness. God's love is the source, not the reward, of Christian love (1 John 4:7-8).
He that loveth not knoweth not God; for God is love.
God showed his love in Jesus
The Bible does not leave God's love as an abstract idea. It points to Jesus. God sent his Son into the world so that people might have life through him, and Jesus' death deals with the reality of human sin (1 John 4:9-10). Love, in this sense, moves towards people in need and bears a real cost.
Paul makes the timing especially striking. Christ died for people while they were still sinners, not after they had made themselves worthy (Romans 5:8). God's love is not careless approval of everything we do. He loves enough to rescue, forgive, and change us.
For God so loved the world, that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.
This love has always been real
God's love did not begin when the world began, or when someone first prayed. Before his arrest, Jesus spoke of the Father's love for him before the foundation of the world (John 17:24). Christians have often seen this as a glimpse of the loving relationship between the Father and the Son.
So God does not need people in order to become loving. He freely gives love. That is why the gospel can be received as a gift rather than a bargain. You do not have to perform your way into being noticed by God.
Receiving love changes how we treat people
God's love gives Christians a new pattern for relationships. Jesus told his disciples to love one another in the way he had loved them, and said that this love would make their connection to him visible (John 13:34-35). It can look like truthfulness, patience, forgiveness, practical care, and refusing to treat another person as disposable.
None of us does this perfectly. Still, the direction matters. First John says that our love for God is a response to his prior love for us (1 John 4:19). If this question feels personal, begin there: look honestly at Jesus, bring your need to God, and keep reading the passages around these verses.
We love him, because he first loved us.