“Don’t Argue on the Way!”
After Joseph revealed himself to his brothers, he told them to return to Jacob, their father, and bring him down to Egypt.
Before the brothers left on this mission, the Torah describes that Joseph admonished them thus:
“He escorted his brothers off and they went. He said to them, ‘Don’t argue on the way.’”
Why was this warning necessary?
The simple reason for this warning, Rashi explains, was to prevent them from arguing about who was responsible for Joseph’s sale into slavery and the grief it brought to their father.
However, Rashi’s preferred explanation of Joseph’s instruction is mentioned in the Talmud: he cautioned them against having a discussion of matters of Halacha-Jewish law!
This event occurred hundreds of years before the Torah was given but that does not pose a problem. Rashi had already informed us of the Talmudic tradition that G‑d exposed the Patriarchs to the teachings of the Torah even before it was formally given centuries later at Mount Sinai.  Rashi adds that Jacob had also been teaching Torah to Joseph.
The problem with Rashi’s commentary, however, is: what would have prompted Joseph to be concerned that his brothers might get into a scholarly discussion about matters of Jewish law? Why the need to warn them about such an unlikely threat to their safety as getting into a discussion of Jewish law?
Simply put, one could say that a heated discussion about Jewish law, or any other subject for that matter, on their journey could distract them.  This was much like today’s warnings against texting while driving or similar distractions which could cause an accident.
However, even if this was a valid concern, the question still remains, why did the Torah find it necessary to tell us that Joseph gave them this practical advice? The Torah does not report on every detail of the conversations between Joseph and his brothers; it just gives us some of the salient details that relate to the relationship between Joseph and his brothers. Furthermore, even those details are mostly left out of the Biblical narrative and have been preserved through our oral tradition; only later were they committed to writing in the Talmud and Midrash.
Why then, one may ask, did the Torah go out of its way to reveal that Joseph’s conversation with his brothers concerned a remote danger?
Furthermore, if indeed his concern was a legitimate one, why hadn’t their father Jacob given them this  advice when they first left for Egypt so that they would stay safe on the road?
Joseph’s Extraordinary Virtue and Sensitivity
Perhaps the fact that this was a far-fetched concern is precisely the message the Torah wishes to convey to us. In so doing, it reveals to us the essence of Joseph’s sterling and holy personality.
Joseph’s warning to them about discussion of matters of Jewish law, even though the danger to them was so remote, demonstrated Joseph’s sensitivity and extraordinary concern he had for their well-being.
Indeed, this is an incredible commentary on Joseph. After all the brothers did to him by conspiring to kill him and then selling him into slavery, Joseph did not harbor the slightest grudge. Moreover, he exhibited profound concern for their safety and well-being. He was concerned about the remote possibility that they could be harmed by an innocuous discussion of Jewish law!
Although Joseph had already shown them that he bore no grudge and had completely forgiven them, his brothers could have thought that his words were only a façade. They might have felt that his words were insincere and that he still harbored a grudge.
By showing concern for their safety in such an unexpected manner, Joseph sent them the message that he cared for them deeply. 
Joseph is therefore held up by our Sages as a model of virtue for his total control over his emotions. Instead of feeling hatred and desiring revenge, Joseph went to the other extreme, showing sensitivity and concern for his brothers’ well-being in a way that even Jacob their father had not!
The lesson for us here is that we must aspire to follow in Joseph’s footsteps. As difficult as it may be, we must be able to forgive those who have offended us and even show them magnanimity. While we cannot control which emotions enter our minds, we can control which emotions we allow to live in our minds rent-free. Ultimately, our minds have the capacity to control and even transform our feelings.
This lesson is especially relevant in these last days of exile before the Messianic age, when we will harbor feelings of love exclusively.
Our mission today is to live that way now!
12 Tribes: 12 Approaches 
One may explain Joseph’s unusual admonition to his brothers in another, deeper, way based on the Chassidic analysis of the distinction between the roles of the Patriarchs and the 12 Tribes.
Until the moment Joseph revealed his identity, his brothers were under the impression that there was only one path to life. That was the path charted by Abraham, Isaac and Jacob. It is true that Abraham, Isaac and Jacob were not identical men. Abraham represented the trait of kindness, Isaac that of awe, and Jacob the trait of compassion; however, they complemented each other rather easily. Isaac contained elements of Abraham’s kindness and Abraham possessed elements of Isaac’s awe. Jacob was a perfect blend of Abraham’s and Isaac’s traits.
The Patriarchs essentially represent a uniform message and agenda for the future of the Jewish people.
Their unified message was crucial and lay the foundation for the giving of the Torah at Mount Sinai. The objective of Torah was to reveal G‑d’s oneness to the world. Thus, the ideas of unity and uniformity permeate all aspects of Judaism. We affirm G‑d’s oneness each time we say the Shema. We also extol the Torah as one Torah and Israel as one people. Judaism is, first and foremost, a radical exposition of unity.
All Jews trace themselves back to all three Patriarchs. We all possess all of their traits. This is why our Sages stated: “We do not refer to anyone as our fathers except for the three.” While each Jew can trace himself or herself back to one of the 12 Tribes, we are all uniformly the children of Abraham, Isaac and Jacob. This means that we are not just descendants of the Patriarchs; we are like their children, who have inherited the spiritual DNA from all of them.
That is not necessarily the case with the 12 Tribes. We may have inherited the spiritual DNA of one of the tribes, but not all of them. The tribes represented the individuality of each Jew’s path to fulfilling his or her mission.
To be sure, the 12 Tribes represent 12 diverse approaches to serving G‑d within the framework of Halacha. The 12 approaches must each be permeated with an overarching principle: the diversity within Judaism cannot compromise the Divinity of all parts of the Written and Oral Torah.
Within that unity, however, there are multiple approaches that parallel the multiple personality traits that exist within humanity.
It may be suggested that Joseph’s brothers were unaware of their status as progenitors of individualism and diversity. In their minds, they were tasked to seek total uniformity.
Based on their understanding, they could not fathom that Joseph had a totally different role and mission, which placed him in a superior position vis-a-vis his brothers.
Only now that they had seen Joseph’s rise to the position of leader of Egypt and sustainer of Jacob and his family, did they realize that not all brothers were created equal. They each had an individual role, which allowed them, nay, required of them, to forge an individualistic understanding of their role in life and that Joseph’s role was markedly different and even superior to theirs.
Focus on Unity, Not Division
We can now understand why Joseph told his brothers not to discuss Halacha on their trip back to Jacob.
Joseph realized that his brothers finally recognized that there are divergent approaches to Halacha, which means “a path of life.”  He knew that they would begin to focus on the things that separated them, at the expense of that which unites them. 
Joseph therefore admonished them not to argue about their differences at this point, where they were returning to their father Jacob in the Land of Israel. In this trip, the focus, Joseph intimated, has to be on the unified objective to return to Israel and bring back their father Jacob and all his household. The focus should be on Jacob, not on their difference, as important as those differences may be.
Walking on a Tightrope
The lesson for our times is obvious and powerful.
We must recognize that our generation has an overarching and unified goal around which everything else must revolve. It is our final push over the top for Moshiach and the Redemption that should permeate all of our lives.
While Torah and Mitzvos have not changed as a result of our proximity to Moshiach’s coming, our focus has changed. The Rebbe taught that we are the final generation of exile and the first of the Era of Redemption. Notwithstanding all of the legitimate and admirable differences in our approach to our spiritual endeavors, our unified objective now has to be to bring the Redemption. Every Mitzvah we do should be permeated with a sense of how it will bring the Divine into the world, which, in the aggregate, will transform the world into the one that G‑d envisioned at the beginning of Creation.
And while that was not necessarily the focus in bygone times, today that has changed because we are so close to the final thrust into the Messianic Era.
The Rebbe, the Joseph of our generation, has told us to focus on the goal.
Like the tightrope walker, we must focus all our attention on crossing to the other side!