Yaakov's bittersweet tears

When the brothers came back to tell Yaakov that Yosef is alive and is the ruler in Egypt, the Torah tells us (45:26) that he did not believe them:

וַיַּגִּ֨דוּ ל֜וֹ לֵאמֹ֗ר ע֚וֹד יוֹסֵ֣ף חַ֔י וְכִֽי־ה֥וּא מֹשֵׁ֖ל בְּכׇל־אֶ֣רֶץ מִצְרָ֑יִם וַיָּ֣פׇג לִבּ֔וֹ כִּ֥י לֹא־הֶאֱמִ֖ין לָהֶֽם׃

Yet, one pasuk later, the Torah tells us that when they repeated Yosef's message and he saw the wagons that Yosef sent, he changed his mind:

וַיְדַבְּר֣וּ אֵלָ֗יו אֵ֣ת כׇּל־דִּבְרֵ֤י יוֹסֵף֙ אֲשֶׁ֣ר דִּבֶּ֣ר אֲלֵהֶ֔ם וַיַּרְא֙ אֶת־הָ֣עֲגָל֔וֹת אֲשֶׁר־שָׁלַ֥ח יוֹסֵ֖ף לָשֵׂ֣את אֹת֑וֹ וַתְּחִ֕י ר֖וּחַ יַעֲקֹ֥ב אֲבִיהֶֽם׃

What caused the shift in Yaakov's attitude?

Rashi fills in the gap with a Midrash that says that by sending wagons, agalos, Yosef was communicating to his father that he remembered the sugya of eglah arufah that they had been learning together all those years ago.  When Yaakov heard this, he accepted that "od Yosef chai," that Yosef was spiritually still alive.  Netziv and Chizkuni stick closer to pshat.  טורח רב כזה אין לחוש לשקר -- all the trouble that had been gone through to send the wagons proved that the message was not some lie someone dreamed up, but was the truth.

The Chasam Sofer has a different approach to this whole sugya.  Let's put it in today's terms: everyone wants a vaccine shot.  Imagine a long lost relative that you hadn't seen for years makes contact again, and lo and behold, you find out that he went to medical school and he worked on creating the covid vaccine and can move you right to the front of the line.  Who would not be dancing in that situation?  Who would not say this is hashgacha pratis?  But that's not how Yaakov Avinu thought.  His family was desperate for food just like everyone else, but ha'yad Hashem tiktzar?  Eliyahu haNavi came to the Isha Tzorfatit who had only a small jug of oil and a little flour left and he made a miracle and it lasted throughout the famine of that time (Melachim I:ch 17).  Surely Hashem could find some way to sustain the family of Yaakov Avinu that did not necessitate Yosef having to become the viceroy of a strange foreign land.  It just didn't make sense that all this should happen so Yosef could be the one providing everyone with dinner.

When Yosef meets his father down in Egypt, Yaakov sees him and says:  וַיֹּ֧אמֶר יִשְׂרָאֵ֛ל אֶל־יוֹסֵ֖ף אָמ֣וּתָה הַפָּ֑עַם אַחֲרֵי֙ רְאוֹתִ֣י אֶת־פָּנֶ֔יךָ כִּ֥י עוֹדְךָ֖  חָֽי Why is Yaakov talking about death and crying (as it says in the previous pasuk) at this moment which should be filled with joy?  Chasam Sofer explains (see Ramban and this post) that Yaakov saw this man dressed in Egyptian garb approaching him and he did not know who it was.  It was when Yosef revealed his face that Yaakov finally recognized his son.  Yes, there was joy, but it was bittersweet -- a son dressed like an Egyptian!?  Yes, Yosef had to dress that way because it was necessary for his position, yet af al pi kein...   אַחֲרֵי֙ רְאוֹתִ֣י אֶת־פָּנֶ֔יךָ Yaakov said -- the face I recognize, but the rest of the levush and all the trappings, this is foreign and unfamiliar.  

What ultimately changed Yaakov's mind and convinced him that this was part of Hashem's plan was hearing the full message and seeing the wagons.  This was about far more than escaping the famine.  The full message was that it was time for Yaakov himself to pack all his belongings and come down to Egypt, to enter in the the galus that would hold his children prisoner for years and years to come.  That transition required Yosef to first go down to Egypt to pave the way; to show that Egypt's challenges could be overcome, and to attain a position from which he could help his family have a soft landing into foreign territory.