Only here in the New Testament. Frequent in classical Greek in the sense of a pale or stake. It occurs once in Euripides, meaning a stump (“Bacchae,” 983). It is a stake for a palisade, or for impaling; a surgical instrument; the point of a fish-hook. In the Septuagint it occurs three times, translated thorn in Hos 2:6, where, however, it is distinguished from ἀκάνθαις thorns; brier in Eze 28:24, and prick in Num 33:55. Nine different Hebrew words are rendered by thorn, for which, in the great majority of cases, Septuagint gives ἄκανθα. The rendering thorn for σκόλοψ has no support. The figure is that of the impaling stake. Herodotus, alluding to this punishment, uses ἀνασκολοπίζειν (i., 128; 3, 132). In the ninth book of his history, Lampon says to Pausanias: “When Leonidas was slain at Thermopylae, Xerxes and Mardonius beheaded and crucified (ἀνεσταύρωσαν) him. Do thou the like by Mardonius.... for by crucifying (ἀνασκολοπίσας) thou wilt avenge Leonidas” (ix., 78). The verb seems, therefore, to have been used interchangeably with crucify; and clear instances of this occur in Philo and Lucian. At least one text of the Septuagint gives ἀνασκολοπίζω in Est 7:10, of Haman's being hanged. See further, on Gal 2:20. The explanations of the peculiar nature of this affliction are numerous. Opinions are divided, generally, between mental or spiritual and bodily trials. Under the former head are sensual desires, faint-heartedness, doubts, temptations to despair, and blasphemous suggestions from the devil. Under the latter, persecution, mean personal appearance, headache, epilepsy, earache, stone, ophthalmia. It was probably a bodily malady, in the flesh; but its nature must remain a matter of conjecture. Very plausible reasons are given in favor of both epilepsy and ophthalmia. Bishop Lightfoot inclines to the former, and Archdeacon Farrar thinks that it was almost certainly the latter.
Messenger of Satan (ἄγγελος Σατᾶν)
The torment is thus personified. Messenger is the word commonly rendered angel in the New Testament, though sometimes used of human messengers, as Luk 7:24, Luk 7:27; Luk 9:52; Jam 2:25; see also on the angels of the churches, Rev 1:20. Messenger and Satan are not to be taken in apposition - a messenger who was Satan - because Satan is never called ἄγγελος in the New Testament. Messenger is figurative, in the sense of agent. Satan is conceived in the New Testament as the originator of bodily evil. Thus, in the gospel narrative, demoniac possession is often accompanied with some form of disease. Compare Luk 13:16; Act 10:38, and see on 1Co 5:5.
Connect with messenger, which better suits depart; not with thorn, which would be a confusion of metaphor, a stake buffeting. For the verb, meaning to strike with the fist, see Mat 26:67; Mar 14:65; 1Pe 2:20. Compare Job 2:5, Job 2:7, where the Septuagint has ἅψαι touch, and ἔπαισε smote.