*Minor differences ignored. Grouped by changes, with first version listed as example.
So it was alway,.... Night and day, as long as the people of Israel were in the wilderness, see Exodus 13:21,
the cloud covered it by day: the phrase, "by day", is not in the text, but is easily and necessarily supplied from Exodus 40:38; and as it is in the Targum of Jonathan, and in the Septuagint, Vulgate Latin, Syriac, and Arabic versions, and which the following clause requires:
and the appearance of fire by night; when as a cloud it could not be because of the darkness of the night; as in the daytime it could not be discerned as a body of fire or light, because of the light of the sun; but being seen under these different forms, was serviceable both by day and night, for the following purposes.
The covering of the dwelling, with the cloud which shone by night as a fiery look, was constant, and not merely a phenomenon which appeared when the tabernacle was first erected, and then vanished away again.
*More commentary available at chapter level.