Likutei Sichos vol. 15 page 422 ff. Parshas Vayechi really is about Ya’akov’s passing, yet it is called Vayechi- that Ya’akov lived his best years there! The idea is that life is eternal, and that is only in, and with, God, and only when Ya’akov showed his true connection to Hashem was he truly alive. This happened as he passed in Egypt and was seen in his children. He couldn’t reveal the Ketz to them for the same reason.
