3. Then Moses said to Aaron, "This is what the Lord spoke, [when He said], 'I will be sanctified through those near to Me, and before all the people I will be glorified.' " And Aaron was silent.
Rashi - And Aaron was silent: [and did not complain. Consequently,] he was rewarded for his silence. And what reward did he receive? That God addressed him exclusively in the [ensuing] passage regarding those who drink wine [as verse 8 says, “And the Lord spoke to Aaron, saying…”]. — [Vayikra Rabbah 12:2]
Wine represents the opposite of silence. The Talmud states that "when wine enters, secret emerges." It is well known that drunk people often speak more than they are supposed to. They lose their inhibitions and a secret side of them comes out. Sometimes this side can be quite ugly. People's feelings get hurt, others get slandered (Lashon Harah), etc. The worse part of it all is that what is said cannot be retracted. The words leave an indelible mark for all times. It is interesting that this year we read about this account almost immediately after Purim, when perhaps many of us would have been better off keeping a few of our drunken words to ourselves. Also, in the face of so many controversial issues facing our society, particularly in Israel today, we must be very careful with our words and avoid conflict as much as possible.
Aharon's silence represents his quintessential quality of "loving peace and pursuing peace," as mentioned in Pirkei Avot. It also represents the quintessential aspect of the Sefirah of Hod, associated with Aharon. Hod (glory, acknowledgement), shares the same root as the word Hoda'ah, thankfulness, as well as acquiescence. Reflecting on the words (above) told to him by Moshe, Aharon understood that ultimately Hashem had a plan, even if Aharon himself could not fully grasp it.
While Rashi's comment in and of itself is enough to show just the greatness of Aharon's silence, it is worth taking a closer look at the words of the ensuing passage directed solely to Aharon. It includes more than just an admonition against drinking wine in the Temple:
8. And the Lord spoke to Aaron, saying, 9. Do not drink wine that will lead to intoxication, neither you nor your sons with you, when you go into the Tent of Meeting, so that you shall not die. [This is] an eternal statute for your generations, 10. to distinguish between holy and profane and between unclean and clean, 11. and to instruct the children of Israel regarding all the statutes which the Lord has spoken to them through Moses.
May we all internalize this quality of Aharon, so that we may be more at peace with one another, and make life a little easier for Mashiach when he comes.