וּמֹשֶׁ֗ה בֶּן־מֵאָ֧ה וְעֶשְׂרִ֛ים שָׁנָ֖ה בְּמֹת֑וֹ לֹֽא־כָהֲתָ֥ה עֵינ֖וֹ וְלֹא־נָ֥ס לֵחֹֽה׃
און משה איז געװען הונדערט און צװאַנציק יאָר אַלט, װען ער איז געשטאָרבן; זײַן אױג איז ניט געװען טונקל, און זײַן פֿרישקײט איז ניט אַװעק.
Rashi
לא כהתה עינו HIS EYE WAS NOT DIM — even after he had died (Sifrei Devarim 357:34).
Chizkuni
לא כהתה עינו, “his eye had not become dim;” he had exuded light until the end of his days, as he had when he had returned to earth from Mount Sinai on the last occasion.
Ibn Ezra
The heh in his moisture replaces a vav ; compare “his tent” [Genesis 9: 21]. The word comes from “fresh” [Genesis 30: 37]. Most elderly men are defeated by the forces of dessication.
Or HaChaim
צוטריטלעך נאָר פֿאַר פּרעמיום־מיטגלידערRabbeinu Bahya
צוטריטלעך נאָר פֿאַר פּרעמיום־מיטגלידערSiftei Chakhamim
צוטריטלעך נאָר פֿאַר פּרעמיום־מיטגלידערRav Hirsch
צוטריטלעך נאָר פֿאַר פּרעמיום־מיטגלידערRashi
ולא נס לחו means, nor did the life-sap that was in him depart (Sifrei Devarim 357:35): decomposition had no power over him (had no effect on his body), and the appearance of his face had not changed.