Scribes say Jesus is from Satan.
Jesus says that is the unforgivable sin - it's the same as saying the Holy Spirit is an unclean spirit.
Jesus renounces His family, since they think He's crazy.
Sins this reveals
Relying too much on the opinion of man.
Arguing with Jesus instead of accepting His Words.
These are the two groups that humanly speaking would have most impact on Jesus. They say He's nuts and from the devil. But Jesus knows His mission, and they do not. He does not waver when people important to Him reject Him.