"For God loved the world so much that he gave his one and only Son . . ."

Love's chief element is giving. To give from one's surplus, from one's abundance is cheap. But to give what is irreplaceable is costly. The Firstborn son in an Ancient Near Eastern family was tantamount to the father's giving up himself; it was an unthinkable sacrifice. It illustrates God's measureless sacrifice in giving us Jesus. The Christian God's generosity costs him everything.