After Yosef reveals to his true identity his brothers, he commands them to go home and inform their father Yaakov that he is still alive. When they reveal this information to him, the Pasuk says (45:26), “Lo He’emin Lahem,” “he did not believe them.” The next Pasuk, however, says, “Vayar Et Haagalot… Vatichi Ruach Yaakov,” “and when he saw the wagons… the spirit of Yaakov was revived.” This Pasuk raises an obvious question: why did the wagons convince Yaakov that Yosef was still alive?
Rashi (ad loc.) explains that before Yosef was kidnapped, the last thing that he had learned with his father was the concept of Eglah Arufa. The Torah in Devarim 21:1-9 explains what to do if a person is found dead between cities, and no one knows who was responsible. The Torah commands that the elders of whichever city the body is closest to must take a young calf and kill it in a special ceremony. Since the word in Hebrew for calf (Eglah) is spelled the same as the word for wagon (Agalah), the wagons Yosef sent were symbolic of the Eglah Arufa. However, this explanation only makes sense if the wagons were not inherently necessary, and were sent for symbolic reasons. But given that they were sent to take Yaakov to Egypt, how do they symbolize Yosef’s learning about Eglah Arufa with his father?
Rabbenu Bachya believes that there is a deeper meaning to the connection between the wagons and the Eglah Arufa. Why do the elders of the city have to kill the calf in atonement in the first place? After all, they probably had nothing to do with the death! Rashi explains that since the elders did not pay attention and make sure the person leaving their city was properly protected, they must offer a sacrifice of atonement. The Eglah Arufa is teaching us that even if one indirectly contributes to something negative, he still has an obligation to atone for it. This is what Yosef accomplishes by specifically sending wagons to his father. Yosef is trying to send the message to Yaakov that he regrets that they have been separated for twenty-two years. Despite the fact that it was not his fault, he is asking his father to forgive him. Yosef wants to right the wrong he has been a part of by bringing his father to Egypt so they could one again spend more time together. When Yaakov sees this message, he realizes that it is Yosef trying to bring them back together, and that it must be true that Yosef is still alive.