10 Now whom you forgive anything, I also forgive. For if indeed I have forgiven anything, I have forgiven that one for your sakes in the presence of Christ, 11 lest Satan should take advantage of us; for we are not ignorant of his devices. (2 Corinthians 2:10–11, NKJV)
The sinning Christian we read of in 1 Corinthians 5:1 was disciplined by the Corinthian church, and he repented of his sin (2 Corinthians 2:6-8). Now was the time for forgiving and rejoicing, not recrimination. Satan will seek an advantage against us, even when a Christian repents of sin. Therefore, we must always be alert for his subtle deceptions. We cannot afford to be uninformed and unaware of his strategies to entice us to sin. While we pray to our Father to not “lead us into temptation, but deliver us from the evil one,” we must also equip ourselves with the whole armor of God and “be strong in the Lord,” to “be able to stand against the wiles of the devil” (Ephesians 6:10-11). When someone sins against us and hurts us, but then asks us for our forgiveness, we must fully and completely forgive (Matthew 6:14-15; 18:21-35). Otherwise, we are overtaken by sin, at the very moment we ought to be instruments of God’s mercy and compassion.