"Go toward Moshe to the desert!" (Shemos 4:27) ... Israel says before Hashem, "Who will make you like a brother to me!" (Shir Hashirim 8:1). You find that all brothers hated each other: Kayin hated Hevel, ... Yishmael hated Yitzchak, ... Esav hated Ya'akov, ... the tribes hated Yosef. About which brother(s) did Israel refer to the Holy One blessed be He? Like Moshe and Aharon, as the verse states, "Behold, how good and pleasant is the dwelling of brethren together!" (Tehillim 133:1), [since] they loved and cherished each other. When Moshe took kingship and Aharon priesthood, they did not hate each other. Rather, they were each happy for each one's greatness... (Midrash Tanchuma 27).
The Midrash cites as an example of the brotherly love between these two great leaders the fact that Moshe was hesitant to accept the position as redeemer - famously replying to G-d, "שלח נא ביד תשלח!" (Shemos 4:13) - because he did not want to assume this role of leadership since his older brother, Aharon, had been a prophet in Egypt and Moshe's being chosen as the redeemer might cause him anguish. Hashem responded to Moshe, "Not only would Aharon not be hurt by this, he would be overjoyed!", telling Moshe, "He will see you and be glad in his heart!" (ibid. v. 14).
A related exchange occurs when Aharon is chosen as the Kohein Gadol. Moshe serves as a kohein in the mishkan during the inaugural period of the shivas yemei hamilu'im (Vayikra ch. 8) happily giving over the reins of kehuna to his brother and his sons (ibid. ch. 9) even reassuring Aharon of his worthiness for this role - even in light of Aharon's hesitance because of his involvement with the golden calf - with the words, "Why are you embarrassed, for this you were chosen!" (Rashi, Vayikra 9:7).
Moshe's total mastery of the quality of ayin tova, viewing others' accomplishments and position in a positive rather than a negative light is magnificently manifested in his famous reply to Yehoshua's attempt to stop Eldad and Meidad from prophesying in the camp: "Are you zealous for me? And would it be that the entire nation would be prophets if Hashem would place his spirit upon them!" (Bemidbar 11:29). Moshe, in effect, is selflessly declaring that if each member of the Jewish people would be just like him, he would be elated, not disappointed or jealous.
Envy of another's accomplishments, assets and position is one of the primary negative forces in the struggle for developing a perfected Torah personality. Chazal tell us that alongside desire and the pursuit of glory, this trilogy of human qualities serve as archetypes of sin (see Avos 4:21). Falling into their trap unfortunately qualifies the person as being a student of Bilam Harasha; overcoming them places one in the category of being a disciple of Avraham Avinu (ibid. 5:19).
To be sure, Chazal (Bava Basra 21b) even encourage the positive use of envy for a higher purpose, citing the saying, "קנאת סופרים תרבה חכמה - the envy of scholars will increase wisdom." Seeing the scholarly accomplishments of a fellow Jew can spur an individual to pursue similar achievements. Yeshivos, aware of other yeshivos being more successful, will be incentivized to raise the bar of their educational offerings and environment, and therefore, generally, it is encouraged that multiple yeshivos should open in one town. However, the sefer L'rei'acha Kamocha (Vol. 2, p. 159) notes that there are two kinds of envy. Whereas the first is where A wants something B has but is fine with B having it as well, the second is where A wants something exclusively which B has wishing that B should lose it or desiring to somehow get it from him. The former type of envy is, concerning mundane matters, not formally prohibited according to many poskim, but is not recommended since, being the opposite of a samei'ach b'chelko attitude, will lead to an unhappy life of always trying to "keep up with the Joneses." However, concerning spiritual matters, this kind of envy is, as above, even recommended as an impetus to drive one to higher forms of service of G-d. By contrast, regarding the second type, Ramban (Vayikra 19:18) maintains that it is prohibited as an aspect of the commandment of "V'ahavta l'rei'acha kamocha." Envy of that type is prohibited even concerning spiritual matters.[1]
How does one overcome the natural drive causing jealousy? Whereas no easy solutions exist, it would appear that several attitudinal changes can assist in doing so. Firstly, a sense of profound gratitude for what one already has mitigates jealousy. Chovos Halevavos teaches that a person can always look to others who have it worse off than he does in order to develop gratefulness for that which he does have. Moshe's profound sense of gratitude he felt toward all the people - and even objects - benefiting him presumably also informed his total lack of envy toward his brother and, later, his people.[2]
Secondly, Chazal teach us, "בכל אדם מתקנא חוץ מבנו ותלמידו - a person is naturally jealous of all others except for his student and his son" (Sanhedrin 105b). Why is this distinction true? It would appear that since a person views his student and child as an extension of himself, no envy can exist. Perhaps we can suggest that increasing our awareness of the fact that the Jewish people are all part of the same team and, on a deeper level, are even all part of a common communal soul, Knesses Yisrael, can help implant a new vantage point fostering the treatment of all Jews similarly to the way we would view our own sons and students - as extensions of ourselves, such that their accomplishments are also our accomplishments and their successes are our successes.[3]
Thirdly, realizing that ultimately our lot in life is determined by our loving Father in Heaven, the Master Planner for all of our individual lives and their role in the ultimate destiny of the Jewish people can help foster a more beneficent view of others' achievements and assets. The Talmud (Ta'anis 25a) relates a story about R. Elazar b. Pedas who was extremely indigent. In need of nourishment after a medical procedure, he ate the only food he had, a clove of garlic! After fainting, he had a dream in which he asked Hashem, "How long do I have to suffer in this world?" Hashem replied, "Elazar, my son, would you like me to overturn the world from the beginning so that maybe you will be born in a 'time of sustenance?'". He replied, "All that, and only maybe?!" Rav Aryeh Kaplan[4] explains that this Gemara is teaching us of the profound workings of Divine Providence whereby each individual person serves a different role in the grand scheme of history. If one person's lot would change, that would greatly affect other aspects of the Divine plan rooted in the very fabric of Creation from the beginning of Time. It was this truism that the Almighty conveyed to R. Elazar b. Pedas after which he was resolved to his fate.[5] Such a humbling attitude of recognizing our unique, if different, roles in the great tapestry of existence can assist in reducing envy toward others.
Rav Shlomo Zalman Auerbach zt"l, having heard that a student of his purchased a new apartment, requested to visit. Surprised but honored, the student gladly agreed. Upon visiting, the gadol asked to see all of the rooms, inquiring where different things were put. Again surprised by his Rebbe's inquisitiveness about such mundane matters, the student inquired what motivated his visit and piqued his interest in the particulars of his apartment. Rav Auerbach responded, "There is so much ayin ra'ah (an envious eye) in the world; I wanted to place an ayin tova on your apartment, being happy for you!" May we all learn from our stellar leaders, Moshe's and Aharon's example of ayin tova concerning others' accomplishments and assets and utilize all that we have to serve our Creator individually and together as one nation!
[1] Also see Envy: The Prohibited, the Permissible and the Recommended for further elaboration on these concepts.
[2] Also see Gratitude - The Legacy of Moshe by Rav Zvi Sobolofsky for further elaboration on Moshe's attitude of gratitude in stark contrast to Pharaoh's lack of it.
[3] Also see Yerushalmi Nedarim (9:4) which compares taking vengeance against a fellow Jew to the right hand hitting the left one.
[4] Handbook of Jewish Thought (Vol. 2), Chap. 19, Divine Providence (p. 297).
[5] For his trust in Hashem and not requesting a redo of the world (!), he was promised enormous spiritual reward.