Cap. IX Arg. 11 Sol: Augustine, Prosper, Council of Valence on original-sin remission; baptism seals new-covenant remission of actual sins for the whole course of life (1 John i. 9)
On remission of original sin Augustine agrees everywhere (De pecc. mer. Et remiss. 1.28 and 2.4). Prosper also, ad Cap. Gall. Resp. 2, races the same view. Finally the Council of Valence, cap. 5, proposes this as to be held most firmly. Likewise for remission of actual sins under the new covenant's condition: that is sealed most firmly to every baptized person — not only at the moment of receiving baptism, but for the rest of life's course. Whoever is baptized into the name of Jesus Christ, if he sins after baptism, has in that same Christ's blood, through faith, expiation of his sins prepared (1 John i. 9).
Latin
De remissione peccati originalis habemus Augustinum ubique adstipulantem: De pecc. mer. et remiss. lib. 1. cap. 28. et lib. 2. cap. 4. Prosper etiam ad Cap. Gall. Resp. 2. eandem sententiam amplexatur. Denique, in Concilio Valentino, cap. 5. hoc firmissime tenendum proponitur. Porro, de remissione peccatorum actualium, sub conditione novi foederis impetranda, idem statuendum est: Hoc enim firmissime omni baptizato obsignatur, non solum quoad ipsum momentum quando Baptismum suscipit, sed quoad reliquum cursum vitae suae. Nam quicunque baptizatus est in nomen Jesu Christi, ille si post Baptismum peccaverit, in sanguine ejusdem Christi paratam habet per fidem peccatorum suorum expiationem; 1 Joann. i. 9.