What does Jesus mean in Matthew 6:14–15 when he says that if we do not forgive others, neither will the Father forgive us? If our trespasses are not forgiven, doesn’t that translate into not being “saved”? Although she was a Christian, my mother always said she would never forgive the man that murdered her sister. I often reminded my mom that this would eat away at her. That man killed himself also after committing the murder so my mother never had opportunity for closure through the legal process. If my mother died not forgiving that man, is she not saved?

Jesus had just taught the Lord’s Prayer in the preceding verses, and these words reinforce the Fifth Petition (Matthew 6:12): “Forgive us our debts, as we also have forgiven our debtors.” Jesus will develop this same idea again through the parable of the unforgiving servant in Matthew 18:21–35. Only the forgiving will be forgiven.

As you asked, the stark simplicity of that statement raises uncomfortable questions.

Firstly, how does this conditional forgiveness relate to the gospel of free grace? Do we have to forgive others first and then God responds by forgiving us? No, God always moves first and then we respond. We do not earn our forgiveness in any way; God forgives us first, and therefore we respond by forgiving others.

But in Matthew 6:15 Jesus means if we do not forgive, we can lose the forgiveness given to us. The parable of Matthew 22:1–14 shows that underserving people, “both bad and good,” were invited to the wedding feast, and yet one of those is subsequently ejected for being improperly dressed. An unforgiving heart is improper dress for a Christian.

Secondly, what is the individual case for your mother? Is she saved or not? We must acknowledge the unforgiving attitude was a flaw in your mother’s faith. Yet we also know even flawed faith is still saving faith. We all die with flawed faith because we know perfection is impossible for us in this life. If you are worried about her, be comforted—she can be saved.

At the same time, if a person has just read that as permission to deliberately hold on to some amount of unforgiveness in their own heart, be warned—because a person can be saved while unforgiving does not mean he or she will be.

Now, what does forgiveness actually mean? In v. 12 Jesus used the word ‘debt’ as a picture of the problem. The murderer of your mother’s sister “stole” something from your mom, creating a debt—but he will never repay it. Forgiveness means to acknowledge that reality and give up on trying to collect. The banking industry today speaks with exactly this language when they talk about “forgiving a loan” to someone who cannot repay (again, see the financial parable of Matthew 18:21–35). Without forgiveness, your mom’s well-being is forever tied to this man, and as you noted, it “would eat away at her.”

How can we find the power to forgive? Through the grace of God. Jesus invites us to transfer the unpaid debts of all the people around us to him and to trust that he will repay us with better things. The burden of debt collection is one of the things with which we are “heavy-laden” and from which Jesus can give us rest (Matthew 11:28).

That’s good news, because that’s also how it works for the debt each of us has accrued before God. We are stealers of peace and relationships and property from the people around us, which are all offenses against God who is the Father of those people. But the Father forgives us, that is, he acknowledges he cannot get back from us what we owe, and he collects our debt from his own Son instead. There is a direct relationship between the forgiveness we have received and the forgiveness we offer.