Genesis 46:27
אֲשֶר־שָלַח יוֹסֵף וַיַרְא אֶת־הָעֲגָלוֹת
and he saw the wagons that Joseph had sent.
Why did Jacob overcome his initial skepticism only after he had seen the wagons? Rashi suggests that as evidence that it was indeed Joseph who sent the message, Joseph instructed the brothers to tell Jacob that at the time he left, they were studying the laws of עֶגְלָה הָעַרופָה , the laws pertaining to the heifer whose neck is broken (Deut. 21:1-9). The phrase should be interpreted as, “and he saw the calves that Joseph had sent,” since in reality the wagons themselves were sent by Pharaoh, not by Joseph.
The law of the עֶגְלָה הָעַרופָה involves the Jewish concept of a leader’s responsibility. In the event of an unsolved murder, the elders of the city that is closest to the corpse is obligated to bring a heifer into a rough valley or a brook. There they break the neck of the heifer and say: Our hands have not shed the blood, neither have our eyes seen it. Forgive O Lord! The Mishnah raises the question (Sota 9a): Is it conceivable that these venerable elders would actually shed blood? Instead, what the Bible means is that the elders of the community did not send this wayfarer away without food, nor did they allow him to leave the community unaccompanied.
It is almost frightening to consider how much the Torah demands of the leader. Obviously, the leader is responsible for all his actions. His judgment must be proper; he must not accept bribes; he must act in accordance with the principles of justice and charity. In addition, however, the leader is also charged with responsibility for people and events which seem far removed from his concerns. This is the message of the עֶגְלָה הָעַרופָה .
Jacob knew that Joseph was destined for power (v. 37:11). He therefore took care to study the morality of leadership and power with Joseph.
Jacob was now trying to determine if both his son and his disciple were still alive. A ruler of Egypt, he thought, must certainly be assimilated into the general pagan society. Jacob could not believe that Joseph had preserved his spiritual identity and remained loyal to the teachings he had absorbed in Jacob’s household. Now, when the brothers related the last lesson Jacob and Joseph had shared together, he realized that Joseph remained his disciple as well as his son . Therefore, וַתְחִי רוחַ יַעֲַֽקב אֲבִיהֶַֽם – and the spirit of their father Jacob was revived. Through Joseph’s hint regarding the עֶגְלָה הָעַרופָה , he relayed that he was following Jacob’s teachings: that he was precisely the type of leader Jacob would want him to be. (Boston 1974, Moriah 1974)