If I understand correctly, the Protestants’ claim that Jesus has forgiven you all your sins and that he has promised you the Kingdom of Heaven. This would mean that you could now commit as many sins as you like, be as evil as you wish, because you have already been saved. How can it be possible to believe in this teaching in the Gospels? Could you not be wrong here? Do the Gospels really teach a faith which encourages people to commit sins? What is your view about this? (For by grace you have been saved through faith, and this is not from you; it is the gift of God; it is not from works, so no one may boast" (Ephesians 2:8-9).
Answer: The New Testament itself recognizes the danger of such a complete misunderstanding of its teachings. I recommend the careful reading of St. Paul’s letter to the Romans 5:12-6:23, and his letter to the Galatians 6:1-10. The Epistle of James, which the Catholic Church regards as highly as all the other letters from the Apostles, firmly rejects this misunderstanding. See especially James 1:14-26.
It is the task of the Church Councils to clarify teachings which have led or which can lead to misunderstandings, using not only scripture, but also availing themselves of theology. The following dogmatic constitution of the Second Vatican Council on the Church, “Lumen Gentium” (40), comments the question of grace, good works and sanctification:
“40. The Lord Jesus, the divine Teacher and Model of all perfection, preached holiness of life to each and every one of His disciples of every condition. He Himself stands as the author and consummator of this holiness of life: "Be you therefore perfect, even as your heavenly Father is perfect" (Matthew 5:48)… The followers of Christ are called by God, not because of their works, but according to His own purpose and grace. They are justified in the Lord Jesus, because in the baptism of faith they truly become sons of God and sharers in the divine nature. In this way they are really made holy. Then too, by God's gift, they must hold on to and complete in their lives this holiness they have received. They are warned by the Apostle to live "as becomes saints"(Eph 5:3), and to put on "as God's chosen ones, holy and beloved a heart of mercy, kindness, humility, meekness, patience"(Col. 3:12) and to possess the fruit of the Spirit in holiness (Gal. 5:22; Rom 6,22). Since truly we all offend in many things (James 3:2) we all need God's mercies continually and we all must daily pray: "Forgive us our debts" (Matthew 6:12).”