Comentário sobre Êxodo 18:3

AND HER TWO SONS; OF WHOM THE NAME OF THE ONE WAS GERSHOM. Even though this is not the place where [the narrative of] their birth is told, Scripture here explains the names of the two sons [of Moses — Gershom and Eliezer —] because there was no opportunity to mention the name of Eliezer at his birth, as I have explained in Seder V’eileh Shemoth.⁶¹Above, 4:20. See Ramban there regarding why Eliezer was not named at that time. Gershom’s name, on the other hand, is mentioned in 2:22. Here, Scripture wanted to mention the kindness that the Holy One, blessed be He, had shown to Moses, who was a stranger in a strange land. [When he named his second son], he gave thanks there to G-d for having delivered him from the sword of Pharaoh when he fled from before him,⁶²Ibid., 2:15. [and for making him] now king over Israel, and [because] He drowned Pharaoh and his people in the sea.
The sense of the expression for he said, I have been a stranger, etc. is connected with Moses, who is mentioned in the first verse, [and not with Jethro, who is mentioned in the second verse]. Similarly, the following verse, And the name of the other was Eliezer: for the G-d of my father was my help,⁶³Verse 4. is connected with the expression for he said, [found in the verse before us. It thus reads: “And the name of the other was Eliezer; for he said: for the G-d, etc.”] There are many cases like that.

שם האחד גרשם, the name of the one was Gershom, etc. Although the reason Moses named this son Gershom has already been mentioned in Exodus 2,22, it had to be repeated here in order to inform us that we are talking about the same son already mentioned in chapter 2 (though this may have been 60 years earlier) and not another son (by the same name but born of a different mother).

כי אמר גר הייתי, “for he had said (at that time) ‘I have been a stranger, etc.” Even though this is hardly the place where we would expect to hear about the genealogy of Moses’ children, the Torah introduces the subject now as there had not been an opportunity to inform us that Moses had called his second son Eliezer, seeing that he had not circumcised him prior to his departure from Midian. First he had been too preoccupied with journeying to Egypt, second, because he had that unfortunate encounter with the angel who had threatened to kill him. He had also not been able to give him the name Eliezer as long as he was under the impression that there was still a price on his head, and he was still a fugitive from Egyptian justice, being wanted for murder. The Torah informs us now that when Moses had become aware that there no longer was a price on his head, he named his son in a manner which expressed his thanks to G’d for having saved him from that worry as well as for the other promotions G’d had bestowed upon him.