Rashi cites the Talmud in Sotah 32a that describes the procedure for giving the blessings and curses. Six tribes ascended to the summit of Har Gerizim, and six tribes ascended to the summit of Har Eival. The Kohanim and Leviim stood below in the middle. The Leviim turned toward Har Gerizim and recited the blessing, while both groups responded with Amen. Afterwards, this same procedure was followed reciting the curses, but this time they faced Har Eival.
Horav M. Shternbuch, Shlita, suggests a profound lesson to be derived from this pasuk. The tribe of Levi received no portion in Eretz Yisrael. Indeed, this tribe has been synonymous with a lack of material sustenance. Their whole earthly “possession” consists of the Torah. Looking for support from their brethren, their lot in life has appeared bleak. The other tribes have represented prosperity and good fortune. They are viewed by the “world” as fortunate. Nonetheless, the success or failure of Bnei Yisrael hinges upon the tribe of Levi. Klal Yisrael’s future is dependent upon the tribe of Levi’s devotion to successful Torah study. They stand in the “middle,” effecting blessing or curse.
Bnei Torah may stand at the bottom of the ladder of material accomplishment. Their spiritual achievement, however, is the determining factor for everyone else’s success. As always, appearances may be deceiving. The individual who, according to man’s limited vision, is “suffering” on the bottom of the pole may be at the summit of success in the eyes of the Eternal. Bnei Torah, the spiritual heirs of the tribe of Levi, should be nourished and sustained, so that Klal Yisrael may continue to endure.
