Exegesis:

kai parekaloun auton ‘and they besought him.’ The imperfect tense may either suggest repetition (cf. Plummer, The Four Gospels – a New Translation) or denote an act which may be without result, preferably the latter (cf. parekalesan in v. 32 referring to a request which is granted). parakaleō cf. on 3.18.

hina mē epitaxē autois eis tēn abusson apelthein ‘that he would not order them to go away to the abyss.’ For epitassō cf. 4.36; 8.25.

abussos ‘abyss,’ ‘underworld,’ ‘hell,’ ‘bottomless pit.’

Translation:

Command them to depart into, or because of the context, ‘to command/tell them to plunge-into (Balinese), or, to descend into (Batak Toba), or, to come-out (of the man) and descend into’ (Low Malay). The expression is sometimes rendered by one verb, cf. “order them off to” (An American Translation), “banish them to” (New English Bible, similarly Javanese).

Abyss, or, ‘hole/pit/well that has no bottom,’ ‘unfathomably deep place’ (Bahasa Indonesia). If such renderings would not have the required connotation, one may use terms as, ‘abode of the wicked,’ ‘place where they (i.e. the demons) dwell, or, are punished,’ ‘land below’ (Batak Toba, similarly Bahasa Indonesia KB, lit. ‘layer below’); Sranan Tongo uses, ‘the deep where the earth opens its mouth,’ a term well known from folk tales.

Quoted with permission from Reiling, J. and Swellengrebel, J.L. A Handbook on the Gospel of Luke. (UBS Handbook Series). New York: UBS, 1971. For this and other handbooks for translators see here . Make sure to also consult the Handbook on the Gospel of Mark for parallel or similar verses.