Mark 3:29 in the King James Version
But he that shall blaspheme against the Holy Ghost hath never forgiveness, but is in danger of eternal damnation:
Context
28 “Most certainly I tell you, all sins of the descendants of man will be forgiven, including their blasphemies with which they may blaspheme;
29 but whoever may blaspheme against the Holy Spirit never has forgiveness, but is subject to eternal condemnation.”
30 —because they said, “He has an unclean spirit.”