Kommentar zu Dewarim 3:9

צידנים יקראו לחרמון וגו׳ THE SIDONIANS CALL HERMON SIRION — But in another passage it states, (Deuteronomy 4:48) “Even unto Mount Sion which is Hermon”. So you see it had four names. And why had they all to be written in Scripture? To tell the praise of the land of Israel: that there were four kingdoms (kings) priding themselves in this — one saying, "After me shall it be named", and another saying, "After me shall it be named" (Sifrei Devarim 37:10; cf. Chullin 60b).

HERMON, THE SIDONIANS CALL SIRION, [AND THE AMORITES CALL IT SENIR]. “But in another place Scripture states, even unto Mount Sion which is Hermon.²⁶⁰Further, 4:48. Thus you see that the mountain has four names [Hermon, Sirion, Senir and Sion. Scripture’s reference to this multiplicity of names is] to tell the praise of the Land of Israel because there were four kingdoms priding themselves in this; this one saying ‘After me shall it be called,’ and another saying, ‘After me shall it be called.’” This is Rashi’s language from the words of Agadah.²⁶¹Chullin 60b.
It is indeed possible that this praise [that four nations were vying for this mountain] is correct but the main purport of the verse is to state that the Sidonians, children of Canaan’s firstborn,²⁶²Genesis 10:15. called Mount Hermon “Sirion” when it was formerly in their possession; and the Amorites, who now dwelled there and from whom Israel was to capture it, called it “Senir.” [Senir] is a Canaanite word for “snow,” as Rashi testified about it, and as Onkelos also rendered it, [“mountain of snow”]. And because it is a mountain of snow, also on account of its frigid temperature causing it to be bleak [and unapproachable], it is called Hermon [from the word cherem — “banned”], this being a surname of the mountain. Perhaps the name “Sirion” in the Sidonian language indicates this characteristic while the real name of the mountain [as mentioned by the Torah further on]²⁶⁰Further, 4:48. is Sion. The verse stating, from the top of Senir and Hermon²⁶³Song of Songs 4:8. [which would seem to indicate that these were two separate mountains], really refers to two surnames of the [same] mountain and thus means “from the top of the snow and the bleakness,” or it may mean “from the top of Senir and from the whole mountain.” Similarly, that which is stated in the Book of Chronicles, And the children of the half-tribe of Menasheh dwelt in the land, from Bashan unto Baal-hermon and Senir and Mount Hermon where they increased²⁶⁴I Chronicles 5:23. also means “and Senir and the whole mountain which is Mount Hermon.” Baal-hermon, however, was a city or a tower which they called “Baal,” or perhaps it was the name of one of the Baal-idols that was worshipped there.
It is possible that after Israel was in the Land, names of places were somewhat changed; this mountain was large — and they called the highest part of its summit Senir, and the second part thereof they called Hermon. Or they²⁶⁵I.e., the mountains mentioned in the above-quoted verses from the Song of Songs and the Book of Chronicles. may be other mountains which people after the [period of the] Torah called by these names [Senir, Hermon — and they really represent two separate mountains, but the names mentioned in the Torah indicate different names of but one mountain, as explained above]. There are many cases like this. So also, and the Hermons from the hill Mizar²⁶⁶Psalms 42:7. [would indicate that there were other mountains by the name of Hermon, for otherwise we have no explanation why they called “the Hermons,” in the plural].

צדונים יקראו לחרמון שריון, “The people of Tzidon referred to Mount Hermon as “Siryon. Nachmanides explains that the principal intent of this verse is to inform us that the Tzidonim, the descendants of Tzidon the firstborn son of Canaan, called Mount Hermon while they were still in possession of it, “Siryon.” The Emorite, i.e. the fourth son of Canaan who occupied that region at the time when the Israelites were in the desert, having wrested it from their cousins the Tzidonites recently, called that Mountain Snir, another word for שלג, snow. They, called it thus to indicate that this mountain is almost all the time capped by snow. Seeing that it is so cold up there, it is without vegetation, חרב hence the letters חר in the name חרמון. Perhaps in the dialect spoken by the Tzidonim, the word שריון also reflects the fact that it is freezing cold up on that mountain.