The same kind of ‘seizure’ was denoted formerly by the phrase ἔχει ἀπ’ ἔξω[335], ‘he has it (i.e. a stroke or seizure) from without,’ and the modern compound ’ξωπαρμένος[336] bears obviously a kindred meaning. The exact significance of ἔξω in this relation is difficult to determine. Either it is only another example of the usage already noted in discussing the term ἐξωτικά and implies the activity of one of those supernatural beings who exist side by side with the powers of Christianity and are by their very name proved to be pagan; or else it indicates a difference in the mode of injury by two classes of supernatural foes, the difference between ‘seizure’ and ‘possession.’ Certainly no story is known to me of ‘possession’ by Nereids in the same sense as by devils. The latter take up their abode within a man and are subject to exorcism; the seizure by Nereids is conceived rather as an external act of violence. This is made clear by several terms locally used of seizure. ‘He has been struck’ (βαρέθηκε or χτυπήθηκε), ‘he has been wounded’ (λαβώθηκε), ‘he has had hands laid upon him’ (ἐγγίχτηκε) are typical expressions, to which is sometimes added ‘by Nereids’ or ‘by evil women[337].’ Such phrases clearly convict the Nereids of assault and battery rather than of undue mental influence upon their victims.
Moreover the Nereids, and with them all the surviving pagan deities, are pictured by the peasant in corporeal form, whereas the angels--and there are bad angels, who ‘possess’ men, as well as good--are in common speech as well as in the formal dedications of churches known as οἱ ἀσώματοι, ‘the Bodiless ones.’ There is then an essential difference in the nature of these two classes of beings, which justifies the supposed distinction in their methods of working. For ‘possession’ proper is the injury inflicted, or rather infused, by spirits pure and simple; external ‘seizure’ is the work of corporeal beings. And this distinction was recognised in comparatively early times; for John of Damascus[338] in speaking of στρίγγαι, a peculiarly maleficent kind of witch (of whom more anon), notes as singular the fact that sometimes they appear clothed in bodily form and sometimes as mere spirits (μετὰ σώματος ἢ γυμνῇ τῇ ψυχῇ). It is then to the second interpretation of the phrase ἔχει ἀπ’ ἔξω, as implying external and bodily violence, that the balance of argument, I think, inclines.