The Torah is rich with parables and models for human behavior. The best part is not the successes of its heroes, but rather their challenges and stumblings.

Our Gemara on the top of amud aleph references a disputation between Aharon, Moshe, Elazar and Isamar.  After the death of Nadav and Avihu, there was a sacrifice that remained to be eaten.  Moshe was angry that the sacrifice was not consumed, and feared that this would be another major misstep that could lead to more divine wrath.  Was it not bad enough that Nadav and Avihu already annihilated?  There are lomdishe explanations about the exact nature of the disagreement between Moshe and Aharon over the consumption of this sacrifice, such as if a regular sacrifice should be consumed during aninus (the first day of relative’s death), or if the sacrifice was rendered impure.

Aside from the Lomdus let’s look at the emotional background. This was indeed a tense moment in the leadership of the Jewish people. Aharon‘s two sons at the most glorious moment of their career and the Jewish people's success were instantaneously burned alive. They committed some imperceptible misstep leading to their annihilation as they attempted to enter the holy of holies. 

We are told, the inquest around the uneaten sacrifice is one of only three times that Moshe became angry (Vayikra Rabbah 13:1). What was he angry about? It would seem after Nadav and Avihu were tragically incinerated, due to lack of awareness of the severity of the holiness of the place they were entering, history was about to repeat itself. The remaining surviving sons of Aharon were again on the verge of committing a misstep. Regardless of the lomdus of the argument, Moshe feared these two sons were going to refrain from eating of the sacrifices despite his understanding that they were obligated to do so. They were once again risking the wrath of G-d.

I also must wonder, was there a subtext going on between Moshe and Aharon simmering beneath the surface? We are told by some midrashic sources (see Rashi Devarim 9:20) that the death of Aharon’s two sons was a consequence of his abetting the sin of the golden calf. We are given explanations for how Ahron saw it necessary to temporarily comply with the mob mentality demanding the creation of the golden calf during Moshe‘s absence (Sanhedrin 7a).  Even so, we cannot assume that Aharon’s choices sat well with Moshe.

So you can imagine the psychic forces that Moshe was up against. The worst kind! Fear, panic, and anger. Fear - that his other two nephews would be annihilated due to the same negligence. Panic - that despite his great piety he cannot fully control nor educate even his closest cabinet members to operate on his level. Anger - that once again his brother has failed him.

Considering everything that was going on, it didn’t end too badly. This time. In point of fact, Moshe was incorrect here and everybody was following procedure as is told in the Gemara 

The lesson for us is to respect how easy it is for us to be overcome by powerful emotions of betrayal, panic, fear, and anger that build up over time.  Those feelings stop us from being in the present and evaluating reality as it is occurring. Although Moshe had good reason to fear that another mistake was being made, he did not need to get angry. All he needed to do was ask with genuine curiosity and he would’ve received an explanation.

Many tragic relationship breaches could be avoided by holding off on anger and expressing genuine curiosity. (I must say, in my life I can think of situations where I caused long-term damage by failing to heed this advice.)

A wonderful example of curiosity versus anger comes our way at the beginning of the Torah. When Adam and Chava ate from the tree of knowledge and were hiding because they were naked, of course G-d knew full well that they had transgressed. However, instead of ragefully castigating them, he begins with a question, “Who told you that you were naked? Did you eat of the tree from which I had forbidden you to eat?” (Bereishis 3:11). Rash (ibid 9) Tells us G-d did so in order to enter into a dialogue. What does that mean? It means that G-d could have thundered at Adam and Chava letting them know everything they did wrong, but instead he engaged in a discussion to give them a chance to ponder what they did and possibly explain themselves. Who knows, history might have been different if they responded with greater remorse and less defensiveness. But the lesson is there regardless, that G-d gave them a chance to explain themselves and didn’t start out in a rage.