Is self mutilation a sin?
Yes!!! Since the Lord lives in your body via the Spirit, self mutilation is defiling His temple. The same is true for drunkenness, drugs and gluttony. All defile the Temple. Would you slice the arm of Jesus if he held it out before you? Jesus expects you to treat yourself as you would Him.
Also; are there any tips on how to stop?
Yes!!!
I can do all things through Christ who strengthens me." Philippians 4:13Through prayer: Pray for self control. Pray for perseverance. Our life on earth is so short compared to eternity! Someone who practices self-mutilation should seek out the help of a priest or pastor immediately! Please – don’t wait. Usually when someone is intent on hurting themselves, it is for selfish reasons. There is a belief that by hurting themselves they are also hurting others – which is true! It is hurting others! Please – take this problem to a Christian counselor as soon as possible.