When Paul writes that he is confident in his friend’s obedience, I do not think he is only referring to Philemon’s obedience to Paul’s instruction, because Paul had just said he wanted his friend to accept the runaway slave out of his own heart rather than Paul commanding him (Philemon 1:21-22).
Paul’s reference to obedience is the obedience to Christ’s command to forgive as we have been forgiven (Mathew 6:15, 18:22-35).
Before jumping to conclusions about what forgiveness means look at both scripture references above. In Mathew, the servant that asked for forgiveness had to face the consequences of his actions because he did not show fruit of true repentance. The servant in Philemon showed signs of repentance by returning to his master even though he did not know what the outcome would be.
Forgiveness and grace is offered, but wiping out of the debt is only done when the fruit of repentance is manifest (Mathew 3:7).
