Reply to Faustus the Manichaean

¹⁷ That the flood came seven days after Noah entered the ark; as we are baptized in the hope of the future rest, which was denoted by the seventh day. That all flesh on the face of the earth, outside the ark, was destroyed by the flood; as, beyond the communion of the Church, though the water of baptism is the same, it is efficacious only for destruction, and not for salvation. That it rained for forty days and forty nights; as the sacrament of heavenly baptism washes away all the guilt of the sins against the ten commandments throughout all the four quarters of the world (four times ten is forty), whether that guilt has been contracted in the day of prosperity or in the night of adversity.