1 John 5:16
If any man see his brother sin a sin which is not unto death, he shall ask, and he shall give him life for them that sin not unto death. There is a sin unto death: I do not say that he shall pray for it.
John wrote that if we see another believer sinning a sin which does not lead to death, we can ask and God will spare that individual. The responsibility of the believer is not to judge the individual but to intercede on the behalf of the sinning person and allow God to work in their life.