"We cannot accept that salt should become tasteless or the light be kept hidden (cf. Mt 5:13-16). The people of today can still experience the need to go to the well, like the Samaritan woman, in order to hear Jesus, who invites us to believe in him and to draw upon the source of living water welling up within him (cf. Jn 4:14). We must rediscover a taste for feeding ourselves on the word of God, faithfully handed down by the Church, and on the bread of life, offered as sustenance for his disciples (cf. Jn 6:51). Indeed, the teaching of Jesus still resounds in our day with the same power: “Do not labour for the food which perishes, but for the food which endures to eternal life” (Jn6:27). The question posed by his listeners is the same that we ask today: “What must we do, to be doing the works of God?” (Jn 6:28). We know Jesus’ reply: “This is the work of God, that you believe in him whom he has sent” (Jn 6:29). Belief in Jesus Christ, then, is the way to arrive definitively at salvation.
Pope Benedict 16th on the opening of the Year of Faith, in his Apostolic Letter Porta Fidei