The Catholic Church teaches that the purification of the souls in purgatory can be assisted by the actions of the faithful on earth. Its teaching is based also on the practice of prayer for the dead mentioned as far back as 2 Maccabees 12:42–46. In the West there is ample evidence of the custom of praying for the dead in the inscriptions of the catacombs, with their constant prayers for the peace of the souls of the departed and in the early liturgies, which commonly contain commemorations of the dead. Tertullian, Cyprian and other early Western Fathers witness to the regular practice of praying for the dead among the early Christians. The theological basis for the feast is the doctrine that the souls which, on departing from the body, are not perfectly cleansed from venial sins, or have not fully atoned for past transgressions, are debarred from the Beatific Vision, and that the faithful on earth can help them by prayers, alms deeds and especially by the sacrifice of the Mass.