Genesis 27:2

לא ידעתי יום מותי I KNOW NOT THE DAY OF MY DEATH — R. Joshua the son of Korcha said: When a person approaches the age at which his parents died he may well be anxious five years before and five years after. Isaac was then one hundred and twenty three years old and he said, “Perhaps I shall only reach the age of my mother who died at the age of 127 and I am now within five years of her age: therefore, I know not the day of my death —I may only reach the age of my mother or it may be the age of my father” (Genesis Rabbah 65:12).

And he said, Behold now, I am old, I know not the day of my death:

וַיֹּ֕אמֶר הִנֵּה־נָ֖א זָקַ֑נְתִּי לֹ֥א יָדַ֖עְתִּי י֥וֹם מוֹתִֽי׃