Levi had three sons: Gershon, Kehas, and Merari. Parshas Naso begins by detailing the parts of the Mishkan that were carried by Gershon’s descendants in the wilderness, followed by a list of the objects that were transported by the offspring of Merari. Surprisingly, the parallel passage regarding the children of Kehas is found not in the beginning of Parshas Naso where it would seem to belong, but rather at the end of Parshas Bamidbar. Why is the delineation of the duties of the Leviyim divided between two different Torah portions instead of all being contained within the same portion?
The Ohr HaChaim HaKadosh explains that the task of carrying the components of the Mishkan in the wilderness that was split amongst the three Levite families was not considered one uniform job which was divided three ways. Even though each function appears to be an element of the overall job of transporting the Mishkan, in reality there were three different assignments, each with its own unique focus and attributes. The descendants of Kehas carried the holiest vessels in the Mishkan, including the aron [ark]. Since Chazal teach (Sotah 35a) that the aron miraculously carried those who appeared to be carrying it, this job involved only minimal physical exertion. Gershon’s progeny were in charge of moving the Mishkan’s assorted curtains and coverings, while the job of the children of Merari was the most physically strenuous, as they were responsible for carrying the heavy wooden beams and planks that formed the Mishkan’s walls.
Rav Aharon Yosef Rosen notes that the annual cycle of Torah readings requires Parshas Bamidbar to be read before Shavuos (Tosfos Megillah 31b), while Parshas
