The Greek that is translated as “to fear” or “to be afraid” or similar in English is translated in Ashe as agõõi iwei or “hearing fear.” (Source: David Rowbory)
See also very afraid and fear of the LORD (Isa 11:2).
οἱ δὲ ἠγνόουν τὸ ῥῆμα τοῦτο καὶ ἦν παρακεκαλυμμένον ἀπ᾽ αὐτῶν ἵνα μὴ αἴσθωνται αὐτό, καὶ ἐφοβοῦντο ἐρωτῆσαι αὐτὸν περὶ τοῦ ῥήματος τούτου.
45But they did not understand this saying; its meaning remained concealed from them, so that they could not perceive it. And they were afraid to ask him about this saying.
The Greek that is translated as “to fear” or “to be afraid” or similar in English is translated in Ashe as agõõi iwei or “hearing fear.” (Source: David Rowbory)
See also very afraid and fear of the LORD (Isa 11:2).
Following are a number of back-translations of Luke 9:45:
Exegesis:
hoi de ēgnooun to rēma touto ‘but they did not understand this word.’
agnoeō ‘to understand not’ (cf. Mk. 9.32).
kai en parakekalummenon ap’ autōn ‘and it was concealed/hidden from them,’ i.e. their not understanding what Jesus said was due to an influence beyond their control. parakaluptō.
hina mē aisthōntai auto ‘in order that they might not comprehend it,’ indicating purpose, or, ‘so that they might not comprehend it,’ indicating result, preferably the latter, since the perfect tense of ēn parakekalummenon suggests a situation which makes it impossible for the disciples to understand.
aisthanomai ‘to comprehend’; here used with negative it is synonymous with agnoeō.
ephobounto erōtēsai auton ‘they were afraid to ask him,’ or ‘they were ashamed to ask him,’ preferably the former.
Translation:
They did not understand this saying, cf. on 2.50.
It was concealed from them. A reference to God, or Jesus, as agent may be necessary in some cases, e.g. in Kituba, ‘God had hid it (from them),’ or in Tboli, ‘he did not cause-it-to-be-revealed to them,’ but it is preferable to be less explicit, cf. e.g. ‘the word hid itself from them’ (Kele), ‘it was a riddle to them’ (Leyden), ‘it still was-veiled (lit. having-its-peel, said of words that exalted characters use on the stage, incomprehensible for the common man)’ (Balinese).
Perceive, or, “see its meaning” (Translator’s New Testament), “grasp it” (The Four Gospels – a New Translation, similarly Bible de Jérusalem), or some other synonym of ‘understand.’
Were afraid, or negatively put, ‘did not dare’ (Nieuwe Vertaling), ‘did not have the courage.’
To ask, i.e. for insight; in Chontal the implied direct discourse is made explicit, cf. ‘they were scared, so they didn’t ask him, “What does your word say?” ’
About this saying, or, ‘what he/Jesus said (or, meant, or, meant to say).’
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.