The Catechism of the Catholic Church teaches that mortal sin “destroys charity in the heart of man” (1855) and that “to die in mortal sin without repenting and accepting God’s merciful love means remaining separated from him forever by our own free choice” in a state of existence that we call “hell” (1033). This means that even a Christian who commits a mortal sin can lose his salvation.
But some Protestants think that Hebrews 10:10,14 contradicts this belief, which is held not only by Catholics but by many Protestants. The author of Hebrews says that we “have been sanctified through the offering of the body of Jesus Christ once for all.” The author then says similarly in verse fourteen, “For by a single offering he has perfected for all time those who are sanctified.”
If Christ’s offering has sanctified us “once for all” and “for all time,” so it’s argued, then we don’t need to worry about mortal sins causing us to lose our salvation, since when God justifies us he forgives all our sins—past, present, and future.
How can we meet this challenge?
The first thing we can say is that this passage can’t mean all future sins are automatically forgiven because the Bible elsewhere teaches that there are conditions for having our future sins forgiven.
Consider, for example, Jesus’ teaching in the Our Father: “Forgive us our debts, as we also have forgiven our debtors” (Matt. 6:12). Jesus then gives us commentary:
For if you forgive men their trespasses, your heavenly Father also will forgive you; but if you do not forgive men their trespasses, neither will your Father forgive your trespasses (vv.14-15).
According to Jesus, a condition for having our sins forgiven is that we forgive others. But by making reception of the forgiveness of sins conditional, it can’t possibly be true that our future sins are forgiven. What if we don’t forgive others in the future? Jesus seems to imply that it’s possible for a Christian to choose not to forgive his debtors and thus not be forgiven himself. If our future sins were already forgiven, then such hypotheticals would be unintelligible.
Other elements in the Our Father give support for the ongoing need for forgiveness. Consider that Jesus also instructs us to pray for our “daily bread,” that God’s “will be done on earth as it is in heaven,” that God “lead us not into temptation,” and “deliver us from evil.” Are these requests that we make only once in our Christian life?
If Jesus intends that we make these petitions in the Our Father on an ongoing basis, then it stands to reason that he wants us to pray for forgiveness on an ongoing basis as well. But why would Jesus want us to continuously pray for forgiveness if all our future sins are forgiven from the moment we’re saved?
What Jesus teaches about forgiveness in the Our Father is concretized in his parable about the unforgiving servant in Matthew 18. Jesus tells the story of the servant whose debt of 10,000 talents was forgiven by the king and how the servant didn’t extend the same mercy to those who owed him much smaller debts. Upon discovering the wicked servant’s actions, the king threw the servant into prison.
Given that it would have been impossible for the servant to pay back 10,000 talents, which according to late Anglican New Testament scholar R.T. France is like saying he owed “zillions,” the “prison” most likely represents hell. Similar to his teaching in the Our Father, Jesus then tells his audience, “So also my heavenly Father will do to every one of you, if you do not forgive your brother from your heart.”
This parable teaches us both that there are conditions for receiving God’s mercy and that it’s possible for future sins not to be forgiven if the condition of forgiving others is not met. Jesus’ audience consists of those who already had their sins forgiven, his disciples: “At that time the disciples came to Jesus, saying, ‘Who is the greatest in the kingdom of heaven?’” (Matt. 18:1). If Jesus threatens his disciples with hell for not forgiving their brethren, then he doesn’t intend for their future sins to have already been forgiven.
In the parable, the king forgave the servant’s debts, which the Church has always understood as an illustration of God’ forgiveness for us—the eternal debt of our sin would be wiped away. If it were true that all future sins of saved Christians are forgiven, it wouldn’t have been possible for the servant to be thrown in jail for not forgiving his debtors. How could hell be the destiny of a disciple whose sins had already been forgiven?
We can also look at another passage from the book of Hebrews: “Let us then with confidence draw near to the throne of grace, that we may receive mercy and find grace to help in time of need. (4:16)” If our future sins were already forgiven, this instruction would be unintelligible since there would be no need to approach God’s throne in order to receive his mercy.
The true meaning of Hebrews 10:10,14 is that the grace Christ won on the cross for the forgiveness of sins can be applied to sinners at all times, on the condition that they repent.
The meaning of “once for all” in verse ten becomes clear in verses eleven and twelve, wherein the author contrasts the repeated sacrifices that can’t take away sins with Christ’s single sacrifice for sins:
And every priest stands daily at his service, offering repeatedly the same sacrifices, which can never take away sins. But when Christ had offered for all time a single sacrifice for sins, he sat down at the right hand of God.
The point the author is making is that Christ’s one sacrifice is sufficient to take away our sins (whenever we repent). He doesn’t have to offer himself again to merit the grace that forgives us of any new sins we commit. His death on the cross 2,000 years ago was sufficient.
Concerning verse fourteen, where we read that Christ has “perfected [teteleiōken] for all time those who are sanctified,” in light of the above passages we know that the author can’t mean that our future sins are forgiven. Therefore, he must mean something else.
A plausible reading is that Christ’s sacrifice makes complete provision for Christians of all times to achieve their goal of perfection. Not only does the Greek word teteleiōken (“he has perfected”) allow for such a reading, it would also fit the context that speaks of Christ’s death precluding any further sacrifices for sins.
Furthermore, the phrase “those who are sanctified” can be translated “those who are being sanctified” (as it is in the ESV translation). The present participle suggests that there is an ongoing application of the merits of Christ’s single offering, unlike the Old Testament sacrifices, which needed to be constantly repeated. This militates against the way the challenge interprets the text, since if our future sins were already forgiven there would be no need for a continuous application of Christ’s merits.
As I show in my book Meeting the Protestant Challenge: How to Answer 50 Biblical Objections to Catholic Beliefs, perhaps a reply to our Protestant friends could be, “Is repentance a condition for forgiveness or not?” The bible says it is. The Bible also says ongoing repentance is necessary as well. If there’s any belief that doesn’t jibe with Scripture, it’s the idea that all our future sins are already forgiven.