In that “new and eternal covenant” fulfilled in the New Testament, God identifies Himself in a direct manner: “God is love.”
He demonstrated this by sending His Son, to show us what love is.
~Deus Caritas Est~
“God is love, and he who abides in love abides in God, and God abides in him” (1 Jn 4:16). These words from the First Letter of John express with remarkable clarity the heart of the Christian faith: the Christian image of God and the resulting image of mankind and its destiny. In the same verse, Saint John also offers a kind of summary of the Christian life: “We have come to know and to believe in the love God has for us”.
We have come to believe in God's love: in these words the Christian can express the fundamental decision of his life. Being Christian is not the result of an ethical choice or a lofty idea, but the encounter with an event, a person, which gives life a new horizon and a decisive direction. Saint John's Gospel describes that event in these words: “God so loved the world that he gave his only Son, that whoever believes in him should ... have eternal life” (3:16)