Do not return the insult
Romans 12:17-21 tells believers not to repay evil for evil. Jesus taught enemy-love and blessed people insulted because of Him (Matthew 5:11-12). That does not mean every insult needs an immediate reply.
Ask whether there is an honest concern underneath the joke. Christians have sometimes behaved hypocritically or caused real harm. Acknowledging that truth is not disloyal to Jesus.
When someone wants a real discussion, answer with gentleness and respect (1 Peter 3:15-16). When a group wants entertainment, a calm “I’m willing to talk when we can listen to each other” may be enough.
When the mockery is online
You do not owe every account a debate. Save evidence of threats, use the platform's safety tools, and block someone who keeps using access to harm you. If the person is a friend, ask once whether they want an honest conversation away from the comment thread. A public pile-on rarely becomes a careful search for truth.
Before posting, ask whether your reply sounds like Jesus and whether it helps the person in front of you. Winning applause from your side can still harden the person you claim to love. Sometimes the faithful answer is a clear sentence. Sometimes it is silence followed by steady kindness in real life.
Protect safety and dignity
Repeated harassment at school or work can require documentation and help from a teacher, supervisor, human-resources office, or another appropriate authority. Threats and violence are not a spiritual test you must face alone.
Pray for the person, refuse revenge, and keep ordinary kindness possible. You can love someone while limiting their access to harm you. Read what love your enemies means and how to talk about Jesus.