Genesis 45: How Now Yosef's Cows

After the brothers return to tell Yaakov that Yosef is alive, Yaakov is skeptical. His doubt is only lifted when he sees the agalot—the wagons—that Yosef had sent. The Torah says:“But when they recounted all that Joseph had said to them, and when he saw the agalot that Joseph had sent to transport him, the spirit of their father Jacob revived.”וַיְדַבְּרוּ אֵלָיו אֵת כָּל דִּבְרֵי יוֹסֵף אֲשֶׁר דִּבֶּר אֲלֵיהֶם וַיַּרְא אֶת הָעֲגָלוֹת אֲשֶׁר שָׁלַח יוֹסֵף לָשֵׂאת אֹתוֹ וַתְּחִי רוּחַ יַעֲקֹב אֲבִיהֶם (בראשית מ״ה:כ״ז)The word עֲגָלוֹת (agalot) is usually translated as “wagons,” but it can also mean “cows.” Rashi draws on this second meaning and explains that Yosef was sending a secret message to Yaakov. According to the Midrash, Yaakov and Yosef had been studying the laws of the עֶגְלָה עֲרוּפָה (eglah arufah)—the calf that is ritually killed when a dead body is found between two towns. They had been learning this topic when Yaakov accompanied Yosef partway on his journey to visit his brothers, before Yosef was thrown into the pit.Yosef had expressed concern about his father walking back alone, and Yaakov reassured him that הַקָּדוֹשׁ בָּרוּךְ הוּא would establish a law to honor the solitary traveler—the eglah arufah. Seeing the agalot, Yaakov understood that Yosef was alive and remembered their shared Torah learning.While this is a touching interpretation, the law of eglah arufah would not be enacted for several hundred years. Chizkuni offers a more practical explanation: only a son who truly cared for his elderly father would think to send wagons for the long journey to Egypt. He interprets agalot in its straightforward sense—wagons—noting that it would be natural to send transportation for an old man and young children.Rashbam combines both meanings. He notes that Egyptians revered cows as sacred and had a law forbidding their export, lest they give birth outside Egypt. When Yaakov saw wagons arriving from Egypt with cows, he realized that only someone with royal authority could override such a law. Rashbam’s insight can be taken further: earlier, when the brothers dined with Yosef, the Torah notes that Egyptians would not eat with עִבְרִים (Ivrim). Rashi explains this custom stemmed from the incident with Sarah and Avraham, a story Yaakov surely knew.Thus, when Yaakov saw wagons coming from Egypt—possibly with cows—he understood that not only had a ruler made an exception to Egyptian law, but that someone had convinced that ruler to do so for an Ivri. Only Yosef, an Ivri himself, could have achieved that. This is why Yaakov finally believed that Yosef was truly alive.