What does Matthew 18:34 mean?
This is the last sentence in Jesus' story about the servant who refused to show mercy to his colleague after the king had shown mercy to him. The king had forgiven the first man's debt, which was equivalent to literally thousands of lifetimes of income. That same man then had his fellow servant cast into debtor's prison for a debt of 100 days' wages (Matthew 18:23–33).In response, the angry king now reverses his earlier decision and delivers the servant to the jailers to be imprisoned, as well, until all his debt is repaid. This is, in effect, a life sentence since the servant owes such an impossible sum of money. In the context of Jesus' parable, it is an eternal sentence.
Jesus' troubling application of the parable in the following verse raises questions for all of us. The point of this story is to demonstrate how much we "owe" God on account of our sin. For that reason, those who claim salvation in Christ ought to reflect that understanding by being forgiving towards others. Those who cannot, or will not, be forgiving, give reasons to doubt their relationship with Christ is legitimate (John 14:15).