As the Lord's Prayer comes to a close, we ask to be protected. There is an 'evil one' and we need to be protected from him.
But what does this evil one want to do to us? He's mentioned one other time in the Sermon on the Mount:
"Let your 'Yes" be 'Yes' and your 'No', 'No'; anything beyond this comes from the evil one." (Matthew 5:37, italics mine)
It seems that the evil one likes it when we swear an oath. He likes it when we promise to do something. He likes it when we begin a sentence with, 'to be honest ...'
Maybe you think it's a bit trivial. Shouldn't I be writing about bombings? persecution? the big sins? Yes, that is the risk and it's a big one. But Jesus wants us to be his light for the world, and he wants us to stand  against everything that undermines us. 
We need to pray because we need God's protection or we fall. Peter would find that out later, when Jesus warned him to watch and pray or he would fall into temptation. The Sermon on the Mount tells us about many ways we can fall: anger, sexual desire, revenge, love of money, doing good things for bad reasons, worrying. We're all prone to these things so we need God's protection or we won't be the bright light that God call's us to be.
​So let's pray.

“Do you know what forgiveness means? It’s a decision we make to release a person from the feelings of anger we have against them.” (Mr Rogers in the film "A beautiful Day in the Neighborhood.")
This isn't a film review, but I very much enjoyed this film, which explores forgiveness and what it looks like.
Jesus put forgiveness at the heart of prayer. The word Jesus used for 'forgiveness' is a word that means to leave, to leave alone, or to put some distance in between.
I was brought up in Scotland where we recited the line as 'forgive us our debts, as we forgive our debtors.' When I moved to England I was taken by surprise when people said 'forgive us our trespasses.' I mentioned this to my friends and they  made some comments about the Scots and money.
But in Matthew's gospel it does say, "forgive us our debts." It's not just about the times people sin against us; it's about the times when we feel that we are owed something. To forgive someone, then, is to walk away from the idea that they owe us something, which we often do feel when we are sinned against.
So we pray that God will forgive our debts, and we forgive the debts of others. And we do it at our church together, every Sunday. It matters.