Musar sur Les Nombres 2:7

Yehudah is an example of the first aspect of the pillar Torah that we have cited. Our sages say that during all the forty years that the Israelites wandered in the desert the bones of Yehudah kept turning over within his coffin, and that Moses prayed to G–d שמע ה' קול יהודה ואל עמו תביאנו, "please G–d listen to the voice of Yehudah and restore him to his people" (Deut.33,7). The Talmud Sotah 7 explains that during all these years Yehudah had not been assigned a seat in the celestial academy, had not made proper progress in his studies, and had not succeeded in reconciling what he studied with the halachic decisions. Moses prayed that this should change. In the case of David, however, we find that since his learning matched the halachic decisions it is rated extremely high, and that is why it is said of him וה' עמו, "that G–d was with him, i.e. approved of David's halachic pronouncements. (compare Samuel I 18,14, and Shabbat 56 on that verse.) Yissachar is an example of the second criterion that is required for Torah to be a true pillar supporting the world, i.e. his full time dedication to Torah study. Zevulun is an example of the third criterion, that of supporting Torah scholars financially. To underline the esteem the Torah has for that kind of Torah support, we find that tribe referred to as מטה זבולון, i.e. not ומטה זבולון, to show that he was in a class by himself (compare Baal Haturim on Bamidbar 2,7). He is shown the same deference in Deut. 33,18, when he is mentioned before Issachar, who was his senior.