If you disclose a good or conceal it or you pardon an evil, then indeed Lord Allah is the Forgiving, Capable.
This verse encourages mankind to do good deeds by exposing or secreting. It is told in verse 32: 22: “Who is more unjust than the one who is reminded with Adhikr, and then neglect about It; indeed Lord will revenge these Mujirims". So the believer doesn't pardon any mistake happening from the hypocrites among the Arabic Quran reading Fujjar who are the enemies of the Lord, Messenger, and believers as explained in verse 4: 46. But he should pardon other people belonging to Messenger's community as explained in verse 4: 148. And if he does so Lord will pardon his unintentional offenses. See explanation 2: 271-272; 3: 4, 133-136, and 4: 3.