John Chrysostom
Catena Aurea · Lukasevangelium 3
And he came into all the country about Jordan, preaching the baptism of repentance for the remission of sins; As it is written in the book of the words of Esaias the prophet, saying, The voice of one crying in the wilderness, Prepare ye the way of the Lord, make his paths straight. Every valley shall be filled, and every mountain and hill shall be brought low; and the crooked shall be made straight, and the rough ways shall be made smooth; And all flesh shall see the salvation of God.
(ubi sup.) For as the sacrifice had not yet been offered up, nor had the holy Spirit descended, how could remission of sins be given? What is it then that St. Luke means by the words, for the remission of sins? Seeing the Jews were ignorant, and knew not the weight of their sins, and because this was the cause of their evils, in order that they might be convinced of their sins and seek a Redeemer, John came exhorting them to repentance, that being thereby made better and sorrowful for their sins, they might be ready to receive pardon. Rightly then after saying, that he came preaching the baptism of repentance, he adds, for the remission of sins. As if he should say, The reason by which he persuaded them to repent was, that thereby they would the more easily obtain subsequent pardon, believing on Christ. For if they were not led by repentance, in vain could they ask for grace, other than as a preparation for faith in Christ.