"Then he went home, and the crowd gathered again, so that they could not even eat. And when his family heard it, they went out to seize him, for they were saying, 'He is out of his mind.'" (Mark 3.20-21 ESV)
Verse 21 is hard to believe. His family thought he lost his senses! In his Word Pictures in the New Testament A. T. Robertson comments on the Greek phrase hoi par' autou which here is translated as "his family" (ESV):
"The phrase means literally 'those from the side of him (Jesus).' It could mean another circle of disciples who had just arrived and who knew of the crowds and strain of the Galilean ministry who now come at this special juncture. But the idiom most likely means the kinspeople or family of Jesus as is common in the lxx."
It seems to mean his family because verses 31-32 make it clear that his family is attempting to reach him. Now, it doesn't shock me that his brothers would try to grab him and take him home forcibly because we learn from John 7.5 that they didn't believe in his Messiahship at this point. However, Jesus mother (verse 31) is in the group wanting to grab him!
How could Mary question a son who was born when she was a virgin? Announced by an angel? We humans are quirky and inconsistent beings!
In his Commentary Adam Clarke elaborates on the phrase "He is out of his mind." (Mark 3.21b ESV):
"It was the enemies of Christ that raised this report; and his relatives, probably thinking that it was true, went to confine him. Let a Christian but neglect the care of his body for a time, in striving to enter in at the strait gate; let a minister of Christ but impair his health by his pastoral labors; presently 'he is distracted;' he has 'not the least conduct nor discretion.' But let a man forget his soul, let him destroy his health by debaucheries, let him expose his life through ambition, and he may, notwithstanding, pass for a very prudent and sensible man!"
Isn't it sad? In this world the sinners look sane and the saints look crazy!
Now, if Jesus' family could be so dead wrong about him then it should warn us. Let us be careful before we judge because our judgments can be fallible. He who has ears to hear, let him hear!