창세기 50:26 주석: Rashbam, Sforno, Tur HaArokh & Rabbeinu Bahya

ויישם, as if the Torah had written: ויושם, “he was placed.” We have encountered similar constructions such as in Genesis 9,24 וייקץ נח, where it does not mean “Noach awoke,” but Noach was awoken.” Or, Ezekiel 47,8 the expression המוצאים, where this word is derived from the root יצא and may mean “they were expelled.” (the waters).

ויחנטו אותו ויישם בארון, in the very same casket in which the embalming had taken place. They placed his remains therein and he was never interred in the earth. This is why his casket remained well known throughout the generations. Until “Moses took the bones of Joseph, etc.” (Exodus 13,19)

ויישם בארון, “he was placed in a coffin.” Ibn Ezra draws attention to the vowel kametz under the letter ב which suggests that this coffin was a known entity, drawing the conclusion that Joseph, personally, had prepared his coffin prior to his death.