Charity is at the heart of the Church's social doctrine. Every responsibility and every commitment spelt out by that doctrine is derived from charity which, according to the teaching of Jesus, is the synthesis of the entire Law (cf. Mt 22:36 - 40). It gives real substance to the personal relationship with God and with neighbour; it is the principle not only of micro-relationships (with friends, with family members or within small groups) but also of macro-relationships (social, economic and political ones). For the Church, instructed by the Gospel, charity is everything because, as Saint John teaches (cf. 1 Jn 4:8, 16) and as I recalled in my first Encyclical Letter, “God is love” : everything has its origin in God's love, everything is shaped by it, everything is directed towards it. Love is God's greatest gift to humanity, it is his promise and our hope. (