בְּנֵ֖י מְרָרִ֑י לְמִשְׁפְּחֹתָ֥ם לְבֵית־אֲבֹתָ֖ם תִּפְקֹ֥ד אֹתָֽם׃
Les enfants de Merari, selon leurs familles, par maisons paternelles, tu les recenseras.
Da'at Zekenim
ועצי שטים, “and acacia wood.” Actually, the word שטים is a notrikon, an acrostic composed of the respective first letters in the words: שלום, טובה, ישועה, מחילה, “peace, goodness, salvation, and pardon.” There were some forests in the desert from which the Israelites were able to cut boards which they called shittim. This is also why we read in Joshua 2,1 that “Joshua sent out spies from (the forest around Shittim)” This is also what the prophet Isaiah referred to (Isaiah 41,19) when he wrote (in the name of the Lord) אתן במדבר ארז ,שיטה, והדס, “I will plant cedars in the deserts, acacias and myrtles, and oleasters.“ This is a very lightweight wood and it is very smooth. If we needed any proof that its wood was very light, consider the size of the boards of the Tabernacle’s which were 48 in number. Add two silver sockets for each board, i.e. 96 sockets, add all the upright boards use to surround the courtyard of the Tabernacle, which all had to be transported only by four wagons pulled by eight oxen, as spelled out in Numbers 4,29. Even though each board was 10 cubits high (6 meters) and their thickness was 1 cubit (60cm) and you will realise that unless the wood itself was extremely light, all of this could not have been pulled by only eight oxen. The other four oxen had to pull the weight of the carpets (4 layers) which formed the “roof” of the Tabernacle. We have been told in addition that the בריח התיכון, (Exodus 36,33), the center bolt, used to be Yaakov’s walking staff, the one with which he had crossed the river Jordan on his way to Lavan. Rashi claims that the shittim wood were trees that Yaakov had planted in Egypt as soon as he had come to Egypt, which the Israelites uprooted and took with them when departing from Egypt and which were used now to make the boards for the Tabernacle from. This is also what the liturgist bases himself on. Another interpretation found in the Midrash is that this was wood from the staff Yaakov had .taken with him on the way to Lavan. [I suppose that what the Midrash means is that Yaakov had planted that walking staff in the earth in Charan already, and it had developed. Ed.] This is why he had referred to it in Genesis 32,11, as a symbol of G–d’s providence guiding him during all the years he had been at Lavan. Ed.] It is not surprising therefore that he took those trees with him also to Egypt.
Or HaChaim
-22. וידבר ה׳…נשא, G'd said to Moses: "Take the sum, etc." The Torah had to repeat the line וידבר ה׳ אל משה although it had used this introduction when telling Moses to count the Kehatites. The reason is that in this instance the Torah added the instruction to elevate the status of the clan of Gershon in relation to that of the clan of Merari. The elevation of the clan of Gershon was not of the same nature as that of the Kehatites as compared to the clan of Gershon. The former were distinguished in that they carried the Holy Ark. We would not have known that the clan of Gershon were more distinguished than the clan of Merari had the Torah not employed the term נשא in respect to their tasks. The Torah makes this even clearer when it does not preface the instruction detailing the tasks of the clan of Merari by G'd giving Moses a separate command (compare verse 29). The Torah contents itself with telling Moses to count (תפקד) the members of that clan before detailing their tasks.
Or HaChaim
The Torah continues: ביד איתמר, to make it clear that the exclusion of the firstborn from their erstwhile position as priests affected not only their right to offer sacrifices or to carry the Holy Ark, etc., but even the right to perform the tasks over which Ittamar presided. These comprised duties involving materials of a relatively minor degree of sanctity such as the beams of the Tabernacle and all that belonged to them (Numbers 4,29-33). All of this was a reminder that the sin of the golden calf had not been erased in such a way that no trace of it could be detected. The best proof of this is what G'd said in Exodus 32,34 that whenever He has occasion to punish the Jewish people He will add an extra measure of punishment as part of what they have not yet received.