"This is love: Not that we loved God. It is that he loved us and sent his Son to give his life to pay for our sins." 1 John 4:10
“In this is love..” or another translation could be “In this way is seen the true love."
God didn’t look down and say, “Boy, I see you love me. I think I’ll love you.” Or “You’re a nice guy, I really like that.”
You were rebellious, arrogant, self-centered. God said, “I love you.”
You ignored him, fought him, were bored with him. God said, “I love you.”
You spit in his face, yelled at him, shook your fist. God said, “I love you.”
That’s what John means here.
We see what real love is by looking at what God did. He loved us with a desire to restore us, to make us whole.