“Speak and act as those who are going to be judged by the law that gives freedom, 13 because judgment without mercy will be shown to anyone who has not been merciful. Mercy triumphs over judgment.” (James 2:12-13)
True Christians must be merciful to unbelievers, apostates, and heretics. We must be willing to forgive all people their sins which they commit against us, knowing that we ourselves are horrible sinners saved by grace. We must not judge others, because God is the one judge of the universe.
However, we must still be discerning and recognize sin and evil when it is manifested outwardly. We must warn the sinner of God’s judgment, although we have no authority to judge them ourselves. We are commanded to discipline (but not punish) those in the church who are trapped in sin.
All things must be done with love and mercy, so as to help each other be blameless when we stand before God.