Exodus 19:18

עשן כלו WAS ALTOGETHER ON A SMOKE — This word עָשַׁן is not a noun, because the ש is punctuated with Patach, but it has the meaning of “it was doing something”, similar to and אָמַר and שָׁמַר and שָׁמַע. On this account, its translation in the Targum is תָּנֵן כֻּלֵּהּ “it was altogether giving forth smoke” (תָּנֵן is a verb corresponding with the Hebrew עָשַׁן). and it does not translate it by תְּנָנָא (a noun denoting smoke, corresponding to Hebrew עָשָׁן). But wherever else the word עשן occurs in Scripture it is punctuated with Kametz because it is a noun. הכבשן A FURNACE of lime (i. e. in which lime is burnt and which emits vast quantities of smoke). One might think that the mountain emitted smoke only like such a furnace and not to a greater degree! Scripture therefore states in another passage, (Deuteronomy 4:11) “[And the mountain] burned with fire unto the very midst of the heavens”. Then what reason is there for stating that it smoked only like a furnace? This is said in order to make intelligible to the human ear as much as it can understand: Scripture gives human beings an example (a comparison) which is well-known to them. A similar case is, (Hosea 11:10) “As a lion does He (God) roar”. But who gave the lion power if not He, and yet Scripture compares him only to a lion! But the reason is that we describe Him by comparing Him to His creatures in order to make intelligible to the human ear as much as it can understand. A similar example is: (Ezekiel 43:2) “And His voice was like the sound of many waters”. But who gave the waters a thunderous sound except He, and yet you describe Him by comparing Him to His handiwork — it is to make it intelligible to the human ear (Mekhilta).

וְהַ֤ר סִינַי֙ עָשַׁ֣ן כֻּלּ֔וֹ מִ֠פְּנֵ֠י אֲשֶׁ֨ר יָרַ֥ד עָלָ֛יו יְהֹוָ֖ה בָּאֵ֑שׁ וַיַּ֤עַל עֲשָׁנוֹ֙ כְּעֶ֣שֶׁן הַכִּבְשָׁ֔ן וַיֶּחֱרַ֥ד כׇּל־הָהָ֖ר מְאֹֽד׃

And mount Sinay smoked in every part, because the Lord descended upon it in fire: and the smoke of it ascended like the smoke of a furnace, and the whole mountain quaked greatly.