I have covered what biblical forgiveness is in previous postings, so I'll not go into that again here, but I did think it worthy of the time and space to put down some thoughts on a common error we make in the forgiveness process: excusing the sin because of circumstances.
Excusing offenses and sin because of circumstances is done because we see a person is in the midst of difficulties. When I was in the thick of caring for my mom before she passed on to glory I was frequently stressed and tired. I tended toward being irritable and short tempered with my family after a long day sitting at doctors offices and my parents house. My family tended to excuse my sinning toward them saying, "Mom is stressed because of caring for Grandma, so I won't hold this against her." They thought they were being gracious toward me, and indeed they were, but how did they help me? How was righteousness upheld? Was God glorified in my sin going unconfessed and unrepented of?
Furthermore, when excusing sin becomes a pattern of life it is the perfect breeding ground for bitterness and anger to take root in the heart of the person being sinned against. Excusing the sin is based on circumstances and our "good nature" from day to day. Excusing sin is not the same as forgiving sin.
A child who has been abused by their parent can rationalize that their parent abused them because they were abused as children and they learned this behavior and passed it on. The rationalize that their parent did not learn the right way to discipline or control their anger and so they determine not to hold it against them. However, this does not free the abused person from the anger and bitterness they are feeling in their heart toward their abusive parent. Only the application of biblical forgiveness can relieve that burden.
When we forgive, we are transferring the responsibility for punishment over to God. We are releasing our abuser from our debt and refusing to take vengeance on them. We place all those desires in the hands of God and we trust that He will deal justly with them at some point. This is understanding that God may choose to lavish His rich and wonderful grace upon our abuser as He has done on us, or that the deed done to us may appear to go unpunished throughout this life.
When we forgive rather than excuse we are admitting that the offense done to us really was that bad, it really was sin. It was not a "mistake" or "an accident" or "a bad day."
Be careful not to gloss over the sin of others by excusing it. You are not helping them to repent and change and you are not helping yourself either.