In the course of its history, Israel was able to discover that God had only one reason to reveal himself to them, a single motive for choosing them from among all peoples as his special possession: his sheer gratuitous love. and thanks to the prophets Israel understood that it was again out of love that God never stopped saving them and pardoning their unfaithfulness and sins.
God’s love for Israel is compared to a father’s love for his son. His love for his people is stronger than a mother’s for her children. God loves his people more than a bridegroom his beloved; his love will be victorious over even the worst infidelities and will extend to his most precious gift: “God so loved the world that he gave his only Son.”
God’s love is “everlasting”: “For the mountains may depart and the hills be removed, but my steadfast love shall not depart from you.” Through Jeremiah, God declares to his people, “I haveloved you with an everlasting love; therefore I have continued my faithfulness to you.”
But St. John goes even further when he affirms that “God is love”: God’s very being is love. By sending his only Son and the Spirit of Love in the fullness of time, God has revealed hisinnermost secret: God himself is an eternal exchange of love, Father, Son and Holy Spirit, and he has destined us to share in that exchange.
From the Catechism of the Catholic Church 218-221