(Matthew 18, 21-35) I woke up last Monday morning to hear the radio announcing that it was the 16th anniversary of 9/11. I remembered watching the television as the planes smashed into the twin towers – and, knowing that my son was in New York, sitting frozen until his wife phoned to say he was safe.

In the clearing up of Ground Zero, you may remember, one of the firemen made what appeared to be a remarkable discovery – a page from the bible, burned and fused onto a fragment of steel girder. It was open at the sermon on the Mount where Jesus speaks about forgiveness. You may remember, this was later proved to be a clever hoax but it underlined the subject of forgiveness. It doesn’t detract from the hundreds of true stories of people who were hurt, maimed, bereaved, orphaned, widowed or whose lives were totally disrupted on 9/11, but who somehow managed to forgive the perpetrators of this carnage.

Jesus teaches that Christians should be experts at forgiveness. It’s been said that the mark of a Christian is that he or she “is someone who can’t help forgiving other people” – if only that were true! There’s no way that we can think about all the implications of forgiveness in this brief time – many wonderful books have been written on the subject by people like Terry Waite, Richard Holloway, Desmond Tutu, Nelson Mandela and so on. I’ll give you a taster.

In today’s gospel, we hear how Peter begins to get the hang of this extraordinary Jesus. He knows Jesus doesn’t think or act like other people. “How many times can I be expected to forgive”, he asks? “As many as two or three times?” would have been the normal approach of the rabbis – forgive, yes, but prudently. Once is generous. To be let down again, and to forgive a second time would, according to their teaching, be exemplary. To be foolish enough to get hurt by the same individual a third time, and to forgive even then – that would be excessive.

Peter knows that Jesus thinks big. He wants to get it right. So, he takes a deep breath and asks, “Forgive as many as seven times?" Perhaps he’s thinking, seven ‘s absurd by rabbinic standards, but it might be the number Jesus would like to hear. It’s a holy number, it has the kind of exaggerated quality that Jesus likes – go the second mile, give your cloak as well… We might imagine Peter thinking that Jesus will really like the answer.

But, Jesus’ reply disappoints him. “Not seven times, but seven times seventy!” Four hundred and ninety. This is impossible – unthinkable! In other words, “Forgive beyond your ability to keep track” – forgiveness is to be endless, unlimited, with no exceptions.

Forgiveness doesn’t mean condoning abusive wicked actions – of course, it matters that those planes smashed into the twin towers, that someone drove a van into a crowd of holidaymakers, that my child was sexually abused. Evil actions remain evil and must be challenged. Forgiveness does not mean that we are to be doormats, lying there to be trampled over.

Jesus then explains in this parable, connecting forgiveness to the kingdom of heaven.

There’s this servant, who’ s probably massively been fiddling the books and defrauding his master, the king. He’s caught out, and begs for more time to raise the money to repay. It’s a huge sum – equivalent to several millions of pounds. The king sees the impossible situation the servant’s got himself into, is filled with compassion and wipes out the whole debt – imagine your student loan, your car loan, or your mortgage suddenly being paid off.

The king assumes the debt himself – by leaving it unpaid, he depletes his treasury. It was at staggering cost to himself that he forgave the debt – it was extravagant and precious. You’d think such generosity would, in turn, make that servant generous. Not a bit of it. He finds a colleague who owes him the equivalent of just three months wages and demands instant repayment.

Aren’t we sometimes like this! God forgives us totally – to the tune of millions of pounds worth of misdemeanours and sinfulness – and yet we refuse to let go of the big hurts and wounds, or our lesser gripes and grudges about other people who’ve wronged us in major or minor ways.

Imagine you’re sitting high up in a tree! Listen to what NT Wright says, “Failing to forgive one another isn’t a matter of failing to live up to a new bit of moral teaching.” To fail to forgive means to “cut off the branch we’re sitting on. It’s to deny the very basis of our own salvation – the forgiveness of sin”.

Here’s a true story about two peacemakers, who visited some Polish Christians, ten years after World War II. “Would you be willing to meet with Christians from West Germany?” they asked. So, the two sides met. Then the peacemakers explained, “The Germans want to ask for your forgiveness for what their country did to Poland during the war, and to try to build new relationships”.

Silence! Then one Polish man explained, “It’s impossible. Every stone in Warsaw is soaked in Polish blood! We can’t possibly forgive!”

At the end of the gathering, they agreed to say the Lord’s Prayer together. When they reached, “forgive us our trespasses as we forgive…” there was total silence. Then the Polish man who’d spoken so forcefully explained, tears running down his face, “I have to agree to forgive you. I couldn’t ever pray the Our Father prayer again, or call myself a Christian, if I carried on refusing to forgive. Humanly speaking, we can’t do this, but God will give us strength!”

Eighteen months later, these two groups of Polish and West German Christians met again in Vienna, and began to chat and to build long lasting friendships.

Some of us get things back to front. Part of our reluctance to forgive is because we’ve got the wrong end of the stick – we assume that forgiveness is for the benefit of the person who’s wronged us. We don’t want the one who hurt us to gain anything, so instead of forgiving them, we harbour bitterness, resentment and grudges. But, as the Christians in Poland discovered the first time, often only the person to be healed by forgiveness is the person who does the forgiving. Forgiveness is not meant to burden us – it’s meant to liberate us. Forgiving others is for our own good.

Forgiveness, for Jesus, is not a quantifiable event. It’s a quality – a way of being, a way of thinking and seeing. It is nothing less than the way of Christ. If we’re to follow Christ then it must become our way as well. “Not seven times but seven times seventy”.

One day, Corrie ten Boom was listening to a talk, in reconstructed Germany, by a man sharing the story of how God had forgiven him. To her horror, she recognised him as one of the guards in the concentration camp in which her sister died. He put his hand out to shake hers at the door, and she remembered, “At first, I froze and couldn’t put out my hand to shake his – but in that awful moment, I realised how much God’s mercy and grace had been extended to me. What I couldn’t do in my own strength, I did in God’s strength.”

I’ll leave you with words from CS Lewis, “To be a Christian means to forgive the inexcusable, because God has forgiven the inexcusable in you.”