Rashi
Jewish
1040–1105
“ויאמר כתנת בני AND HE SAID, MY SON’S COAT —is this (i.e. supply the words היא זו after בני). חיה רעה אכלתהו AN EVIL BEAST HATH EATEN HIM — The spirit of prophecy was enkindled within him, for these words may be taken to mean that at some future time Potiphar’s wife would attack him (Genesis Rabbah 84:19). Why did not the Holy One, blessed be He, make known to him (Jacob) that he was still living? Because they had placed under a ban and a curse anyone of them who would make it known, and they made the Holy One, blessed be He, a party with them to this agreement (Midrash Tanchuma, Vayeshev 2) Isaac, however, knew that he was living, but he thought, “How dare I reveal it since the Holy One, blessed be He does not wish to reveal it” (Genesis Rabbah 84:21).”