Exodus 18:4 Commentary: Rashi, Sforno, Or HaChaim & Rabbeinu Bahya

ויצלני מחרב פרעה AND HE DELIVERED ME FROM THE SWORD OF PHARAOH — When Dathan and Abiram made the disclosure regarding the matter of the Egyptian whom Moses had killed and Pharaoh wished to slay Moses, his neck became as a column of marble so that the sword was powerless against him (Shemot Rabbah 1:31; cf. Rashi on Exodus 2:15).

ויצילני מחרב פרעה. At the time Eliezer was born the old king who had wanted to execute Moses had already been dead for a while. This is one of the reasons why the Torah mentioned this death in Exodus 2,23. At that time Moses felt secure from further attempts on his life. Pharaoh’s international police had an exceedingly long reach, just as that of Achav, King of Israel, who had been hunting for the prophet Elijah all over the neighbouring countries of Israel as documented in Kings I 18,10 “is there any kingdom to which the king (Achav) has not sent emissaries to arrange to have to you captured?”

ושם האחד אליעזר, and the name of the one was Eliezer, etc. The reason that Eliezer, Moses' second son is referred to as האחד, "the one," instead of the "second one," is that the reason for Eliezer being named as he was refers to an event which occurred even before Gershom was born. G'd had first saved Moses' life from the sword of Pharaoh before he had enabled him to settle down in Midian.