There are no significant manuscript or translation issues with this verse, though some versions do offer a somewhat different verb tense. In response to the good report that even demons were subject to his name, Jesus said to the 70,
“I was watching Satan fall from heaven like lightning” (Lk.10:18b,
According to the gospel writer, Jesus did use a personal name for Satan, but it’s uncertain what specific name he would have used in Aramaic (as we assume he spoke). Our Greek text uses Σατανᾶς (Satanas), a near transliteration of the Hebrew שָׂטָן first used in the Septuagint to refer to, not devil-figures, but 'opposers’ of ancient Israel. But during the Second Temple Period – likely reflecting Persian influence – evil became personified; ‘the satan’ opposer/accuser of the Hebrew Bible came to be thought of by many Jews as 'Satan', a spiritual being with a personal name, the enemy of God. Jewish pseudepigrapha over the next centuries offered several competing mythologies describing Satan's origin and activities using various names, including Beelzebul, Belial, Mastema, Semyaza, Asael, and Satanael, for example. Some of these texts are identified with particular communities.
The last of these names is important here because in Luke 10:18 Jesus seems to be referring to the story of Satanael from 2 Enoch 29 in which the archangel, who was created from lightning, rebelled and was then hurled from heaven. In this non-biblical book, ‘Enoch’ reports his experience of being taken up to the seventh heaven where God re-told the creation story, different from the biblical accounts and 1 Enoch, including the creation of the heavens on the second day:
“And for all my own heavens I shaped a shape from the fiery substance.
My eye looked at the solid and very hard rock. And from the flash of
my eye I took the marvelous substance of lightning ... and from the
fire I created the ranks of the bodiless armies – the myriad angels –
and their weapons are fiery and their clothes are burning flames. And
I gave orders that each should stand in his own rank. ....
But one from the order of the archangels deviated, together with the
division that was under his authority. He thought up the impossible
idea, that he might place his throne higher than the clouds which are
above the earth, and that he might become equal to my power. And I
hurled him out from the height, together with his angels. And he was
flying around in the air, ceaselessly above the [abyss]. And thus I
created the entire heavens. ...” [Francis Andersen, “2 (Slavonic
Apocalypse of) Enoch,” The Old Testament Pseudepigrapha (J.H.
Charlesworth, ed.; New York: Doubleday, 1983); emphasis added.]
The provenance of current texts of 2 Enoch is disputed, but many scholars believe an early Semitic form of it dates from the time of Jesus. The text is certainly evocative and closely aligns with Jesus' imagery (much more so than Is.14:12 as suggested by Tertullian and Origen). The archangel leader is identified as Satanael in 18:3, the theophoric ‘-el’ ending of his name underlining “his original angelic status,” according to Adrei Orlov, and its removal, described in 31:4, “signifies expulsion from the angelic rank.” According to this story, Satan and his rebel troops are hurled from the highest heaven for thinking they could equal God in power. Depending on one's translation of the very common Greek word ὡς (hōs) in Luke 10:18, Satan falls ‘as’ or ‘like' lightning. Both are true.
This, then, may be the image – and the name – that came to Jesus’ mind when his disciples began to cast out demons, to accomplish on earth what Enoch declared God had already done in heaven.