וְכִלְכַּלְתִּ֤י אֹֽתְךָ֙ שָׁ֔ם כִּי־ע֛וֹד חָמֵ֥שׁ שָׁנִ֖ים רָעָ֑ב פֶּן־תִּוָּרֵ֛שׁ אַתָּ֥ה וּבֵֽיתְךָ֖ וְכָל־אֲשֶׁר־לָֽךְ׃
At doon ay aking tutustusan ka, sapagkat may limang taon pa ng taggutom, upang hindi ka maghirap—ikaw, ang iyong sambahayan, at ang lahat ng iyong pag-aari.”
Ibn Ezra
For he was a son of old age. As it sounds, for he begat him when he was 91. His brother Binyamin they also called "child of old age." And after these two none were born to him.
Rabbeinu Bahya
Rabbi Yoseph in Tossephta Sotah 10,9 points out that the famine resumed after Yaakov’s death and that Joseph’s promise to provide for his brothers (50,21 made after his father had died) was precisely because the famine had resumed at that time. Just as Joseph had used the expression וכלכלתי אתכם, “I will provide for you” in 45,11 at a time when the famine was in full force, so the same expression used in chapter 50 also reflects that the famine was again in full force. Rabbi Shimon did not feel that such an explanation would reflect credit on G’d as it creates the impression that blessings by the righteous are valid only during their own lifetime. His son Rabbi Eleazar nevertheless said that he preferred Rabbi Yoseph’s interpretation to that of his father.