Augustine of Hippo

Honor also the Holy Church, your mother, as the heavenly Jerusalem, the holy city of God; love her, proclaim her. She it is who bears fruit and grows in the whole world in this faith which you have heard, the Church of the living God, the pillar and ground of the truth; she tolerates in the communion of the sacraments the wicked, who are to be separated in the end, from whom in the meantime she withdraws by reason of their diverse manners. For the sake of her grain that now groans among the chaff, whose mass will be revealed in the final winnowing and assigned to the barns. She receives the keys of the kingdom of heaven, that through her, by the blood of Christ and the operation of the Holy Spirit, the remission of sins may be effected. In this Church the soul that was dead in sins will revive, so as to be made alive with Christ, by whose grace we have been saved.