Jesus entered a house to eat with His disciples, and a crowd gathered. Much can be gleaned from His response to the false accusations made by the Scribes (scholars/teachers of the Law); as well as His response to the concerns of His friends/family that occur in this passage.
It appears that the Scribes were trying to figure out what or who was behind Jesus' power to cast out (drive out, eject, expel, send away) demons. Was it that the Scribes saw Him as just a man that they concluded the reason He could cast them out was because He was in league with or possessed by satan? [vs 22 & 23] It doesn't seem to be an issue as to whether or not satan (the prince of demons) and demons existed. [see Mark 3:11] As we read through the Gospels, there are numerous occasions of people, who needed deliverance from demonic activity, coming to Jesus; of parents coming on behalf of or even bringing their children. At every encounter, He commanded the demons to leave; and they had to do as He said. What would the Scribes have thought if they knew that He had just ordained/designated/appointed His 12 apostles and was going to "send them out to preach and to have authority to heal and drive out demons" just as He was doing? [3:14] The Greek word for "devil" is "daimonion" defined as a daemonic being, by extension a diety--devil, god. Webster further defines it as an evil spirit/being, a fallen angel expelled from heaven for rebellion against God; an idol; a false god.
Jesus exposes their erroneous and illogical conclusion by telling them a parable about the "strong man" [read vs. 23-27] From the Scriptures we now know that through His birth Jesus is the one, who entered the "strong man's" house. It was through His death that He "tied up" the "strong man". And it was through His resurrection and ascension that He plundered and carried off the "strong man's" possessions [I John 3:8, Hebrews 2:14 & 15, and Col. 2:15]. He rescued each of us, ransomed us, redeemed us!
Next, Jesus addresses the issue of the precarious position in which they put themselves by making the false accusation of vs. 22 He defines the seriousness of what they actually did when they said in vs. 30 that Jesus "has an evil spirit". He calls it "blasphemy" against the Holy Spirit. The definition for the Greek word "blasphemy" is "vilification (especially against God), evil speaking ... defaming. Webster further defines it is as "speaking of God or the Holy Spirit reproachfully--treating with scorn or contempt..the act of despising...disdain, hatred". This is the sin that will never be forgiven.
Finally, all in one day in Jesus' life, His mother and brothers come. His response to the reason they came??? vs. 34 & 35, looking at those sitting around Him, He said, "...Whoever does God's will is my brother and sister and mother."
He draws us in. Will I, too, sit in His presence? Will I be ready to say "yes" to whatever He directs me to do? Will I join Him in setting people free from the realm of darkness and its effects on their lives? Will I welcome Holy Spirit to live and move in me and through me as He did in Jesus? He compels me to say "YES"; I have to say "YES"! Will you?