The interpretation timeline
Mark 3:21 Douay-Rheims

And when his friends had heard of it, they went out to lay hold on him. For they said: He is become mad.

A.D. 735 – 1849 5 witnesses

Patristic

before A.D. 750
735
A.D.
Bede the Venerable Patristic
c. A.D. 672–735
“(ubi sup.) And blessed indeed the concourse of the crowd, flocking together, whose anxiety to obtain salvation was so great, that they left not the Author of salvation even an hour free to take food. But Him, whom a crowd of strangers loves to follow, his relations hold in little esteem: for it goes on: And when his friends heard of it, they went out to lay hold upon him. For since they could not take in the depth of wisdom, which they heard, they thought that He was speaking in a senseless way, wherefore it continues, for they said, He is beside himself.”
Source

Scholastic

c. 1100 – 1500
1107
A.D.
c. 1055–1107
“That is, He has a devil and is mad, and therefore they wished to lay hold upon Him, that they might shut Him up as one who had a devil. And even His friends wished to do this, that is, His relations, perchance His countrymen, or His brethren. 1But it was a silly insanity in them, to conceive that the Worker of such great miracles of Divine Wisdom had become mad.”
Source

Post-Reformation

c. 1650 – 1900
1771
A.D.
John Gill Reformed
1697–1771
“And the Scribes which came down from Jerusalem,.... Or, "but the Scribes", &c. who had an aversion to Christ, and a different opinion of him: these were they, who having heard much of the doctrine and miracles of Christ, came down from Jerusalem, which lay in the upper, and higher part of the land of Israel, into Galilee, a low country, to make their observations upon him; and take every advantage they could against him, being men, in their way, letter learned, and artful, and cunning: these said, he hath Beelzebub: or, as the Syriac and Persic versions render it, "Beelzebub is in him": sometimes they call him Beelzebub; sometimes say that he cast out devils by him; and here, that he had him, or was in him; Beelzebub possessed him, and assisted him, and there was a confederacy and familiarity between them: and by the prince of devils casteth he out devils; for so they reckoned Beelzebub to be; See Gill on Mat 10:25, Mat 12:24.”
Source
1832
A.D.
Adam Clarke Methodist
1762–1832
“His friends - Or, relations. On this verse several MSS. differ considerably. I have followed the reading of the Syriac, because I think it the best: οἱ παρ' αυτου signify merely his relatives, his brethren, etc., see Mar 3:31; and the phrase is used by the best writers to signify relatives, companions, and domestics. See Kypke in loc. They said, He is beside himself - 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! Schoettgen contends that the multitude, and not Christ, is here intended. Christ was in the house: the multitude, οχλος, Mar 3:20, pressed upon him so that he could not eat bread. His disciples, or friends, went out, κρατησαι αυτον (scil. οχλον), to restrain it, viz. the multitude, to prevent them from rushing into the house and disturbing their Master, who was now taking some refreshment. This conjecture should not be lightly regarded.”
Source
1849
A.D.
1774–1849
“And when his friends had heard of it; [1] literally, his own. We cannot here understand his apostles, for they were in the house with him; but either some of his kindred and friends, or some that were of the same country and town of Nazareth, though perhaps enemies to him. — For they said. It is not certain who said this, whether his friends or his adversaries. — He is become mad. [2] By the Greek, he is not himself. Christ might be called a madman by the Scribes and Pharisees, when he blamed their vices and when he preached with such extraordinary zeal. Or, as the Greek implies, he was thought to be transported out of his wits, and, as the Protestant translation hath it, was beside himself. If they were his friends that said this of him, they did not think so, but only pretended it, that they might get him safe out of the hands of his adversaries. (Witham)”
Source
Modern · 1953 →

The in-app commentary runs from the Fathers to the early-modern record, then stops — that's where the public-domain sources end, not where the reading does. For the modern reading, follow the sources directly.