"Why is Halacha ruled according to the House of Hillel? Because they have the virtue of humility." One must question the words of those [sages] of blessed memory: If the House of Hillel have the virtue of humility, is this a reason to rule Halacha according to them, even if it is not according to their ruling? To resolve this, let us begin with a great principle enunciated by our Sages, concerning one who is humble: "When he studies a precept, his intention is to understand it according to Halacha, and therefore Halacha is ruled as he says".
According to this, the verses in which Moses blessed the Tribe of Levi can be reconciled: " And of Levi he said: Let Your Thummim and Urim be with Your faithful one…They shall teach Your laws to Jacob and your instructions to Israel". At first glance, one would have to ask why Moses gave this blessing only to the Tribe of Levi. Aren't they all the tribes of G-d, having all received the Torah from Sinai and having all learned it directly from Moses? Why, then, did Moses accord the merit of reading the Torah, as well as its teaching, only to the Tribe of Levi?
Our interpretation, however, allows for this to be resolved, as follows: The Tribe of Levi have the virtue of humility. When the Land of Israel was divided among the tribes they did not take any inheritance, as is written in Scripture: "…the LORD is their inheritance" and they were very gladdened by this gift. This is why they are referred to by the term 'faithful', as written in Scripture: 'with Your faithful one', and this is what is meant by 'the intention to understand according to Halacha' as mentioned concerning the House of Hillel, who had the virtue of humility. When they would study with students, they would attend to them until they understood; they never became angry, for such was their virtue.