St. Peter's conversion after he had denied his master three times bears witness to this. Jesus' look of infinite mercy drew tears of repentance from Peter and, after the Lord's resurrection, a threefold affirmation of love for him. The second conversion also has a communitarian dimension, as is clear in the Lord's call to a whole Church: "Repent!"
St. Ambrose says of the two conversions that, in the Church, "there are water and tears: the water of Baptism and the tears of repentance."
Source: Catechism of the Catholic Church (Vatican.va)