to be knocked out of your normal state of mind: overwhelmed with amazement, or, at the far edge, out of your senses.
The word literally pictures standing outside your fixed place. In everyday Greek it covered a wide range, from stepping down out of an office to losing your wits. The Bible fastens on one edge of that range: the way a person is bowled over by something overwhelming. When crowds watch Jesus heal, drive out demons, or raise the dead, they are amazed in exactly this sense, knocked clean out of their composure.
Underneath the different English words lies one picture: being displaced from your normal footing. The same verb runs from the bright astonishment of a crowd at a miracle, through causing that astonishment in others, to the darker edge where a person seems to have left their right mind. That is why two short verses have drawn centuries of argument: when Jesus' family says he is beside himself, and when Paul says that if he was out of his mind, it was for God.
The amazement here is not casual surprise. In the Greek Old Testament this verb was chosen to translate a whole family of Hebrew words for trembling and dread before God, so it carries the weight of awe: the body's involuntary response when God breaks in. Keep that in mind, and the line between overwhelmed wonder and being knocked out of one's senses stops looking like two unrelated ideas and starts to look like one continuum.
Nuances
How to read the word in Mark 3:21, and who its subject is: whether Jesus is charged with being out of his mind, or the verse means something else.
- majorityJesus' family come to seize him because they believe he is out of his mind; their charge is a milder version of the scribes' charge that he is possessed.; R. T. France, The Gospel of Mark, NIGTC (2002); Joel Marcus, Mark 1-8, Anchor Yale Bible (2000); Adela Yarbro Collins, Mark, Hermeneia (2007); Robert A. Guelich, Mark 1-8:26, WBC (1989)
- minorityThe people around Jesus are his associates rather than his family, and the subject of the verb is the crowd, which is out of control, not Jesus.; Henry Wansbrough, "Mark III.21: Was Jesus Out of His Mind?," NTS 18 (1972)
- minorityThe verb is causative here, "he has amazed them," so the verse belongs with the crowd's astonishment rather than with madness.; Drew J. Holland, "A Proposal for a New Reading of Mark 3:21," Journal of Inductive Biblical Studies 4 (2017)
What Paul means by saying that if he was beside himself, it was for God.
- majorityPaul refers to his own genuine ecstatic experience, which is private and directed toward God, set against the sober public ministry he conducts for the church.; Ernst Kasemann, "Die Legitimitat des Apostels," ZNW 41 (1942); Margaret E. Thrall, 2 Corinthians, ICC (1994); Victor Paul Furnish, II Corinthians, Anchor Bible (1984)
- minorityPaul echoes, and ironically concedes, an accusation of madness that has been leveled against him.; Alfred Plummer, Second Epistle of St Paul to the Corinthians, ICC (1915); David E. Garland, 2 Corinthians, NAC (1999); Albrecht Oepke, "existemi," in Theological Dictionary of the New Testament (TDNT) 2:449-460
- minorityThe words are drawn from ordinary criticism of a public leader's manner and speech; Paul is answering the complaint that his speaking was unimpressive, not any charge about religious ecstasy.; Moyer V. Hubbard, "Was Paul Out of His Mind? Re-Reading 2 Corinthians 5.13," JSNT 70 (1998); C. Andrew Ballard, "Tongue-Tied and Taunted," JSNT 37 (2014)