Charles Ellicott Commentary Mark 3:21

"And when his friends heard it, they went out to lay hold on him: for they said, He is beside himself." — Mark 3:21 (ASV)

And when his friends . . .—Literally, those from Him—i.e., from His home. As the “mother and the brethren” are mentioned later in the chapter as coming to check His teaching, we must see in these friends some whom they had sent for the same purpose. To them, the new course of action our Lord had embarked upon seemed a sign of over-excitement, of recklessly rushing into danger. We may, perhaps, see in the random word thus spoken what prompted the more malignant taunt of the scribes in the next verse. They were saying now, as they said afterwards (John 10:20), He hath a devil, and is mad.