Mark 3:30

ὅτι ἔλεγον, etc., because they said: “He hath an unclean spirit,” therefore He said this about blasphemy against the Holy Ghost such is the connection. But what if they spoke under a misunderstanding like the friends, puzzled what to think about this strange man? That would be a sin against the Son of Man, and as such pardonable. The distinction between blasphemy against the Son of Man and blasphemy against the Holy Ghost, taken in Matthew 12:31, is essential to the understanding of Christ's thought. The mere saying, “He hath an unclean spirit,” does not amount to the unpardonable sin. It becomes such when it is said by men who know that it is not true; then it means calling the Holy Spirit an unclean spirit. Jesus believed that the scribes were in that position, or near it.