What does Mark 3:30 mean?

Scribes from Jerusalem (Mark 3:22) have come to Galilee, apparently for the sole purpose of trying to derail Jesus' growing spiritual movement. The Pharisees in Galilee have gone from skeptical (Mark 2:6–7) to questioning (Mark 2:24) to plotting (Mark 3:6). Their compatriots from Jerusalem will have greater influence with the priests.

The Pharisees see Jesus' actions as dangerous and blasphemous. He eats with sinners with no guarantee that the food was prepared properly (Mark 2:15–17). He doesn't make His disciples fast (Mark 2:18–22). And He lets His followers pick and eat grain on the Sabbath (Mark 2:23–28). He even has the audacity to heal on the Sabbath, practically in the same breath He uses to teach in the synagogue (Mark 3:1–6). Worst of all, to the scribes, the people love Him because He has the power to heal and cast out demons. In their eyes, He is a menace who must be stopped.

Because Jesus' teaching and actions do not align with the oral Law, the Pharisees and their scribes do not trust His miracles, particularly His ability to expel demons. His teachings don't reflect what they understand about God, so, they deduce, His powers must not be from God. The only logical conclusion they will consider is that He uses the power and authority of Satan. So, He must be possessed by a demon—an "unclean spirit." That's a profoundly arrogant and sinful approach, one prior verses referred to as "[blasphemy] against the Holy Spirit" (Mark 3:28–29).

The scribes' only hope is to convince the people that Jesus is dangerous before things go too far. His actions could result in the Pharisees losing their position and power among the people. Worse, if Jesus turns out to be a revolutionary, rebellion against Rome would leave all of Galilee flattened and smoking.

Fortunately, not all the Pharisees and priests maintain this line of thinking. Joseph of Arimathea (Mark 15:43), Nicodemus (John 3:1–21; 19:38–42), Paul (Philippians 3:5), and even some of the priests (Acts 6:7) will eventually submit to the leading of the Holy Spirit and believe Jesus is the Messiah and the Son of God.