Because of this conundrum, Rashi says, “If you will act according to My commandment, there shall be no wrath; but if not, that strangers {non-Levites} shall enter this service of {the Levites}, there shall be wrath.” By providing this explanation, Rashi resolves the above-mentioned contradiction in the verses:
The reason why “and there shall be no wrath” is stated in the Torah in conjunction with “The Levites shall encamp around the Tabernacle of the Testimony” is because this arrangement ensures there will be no “wrath” upon “the Assembly of the Children of Israel”:
“If you will act according to My commandment,” meaning: If we perform the mitzvos discussed in this section, which can be summed up in “The Levites shall encamp around the Tabernacle of the Testimony” (as will explained below) then “there shall be no wrath.”
“But if not,” and we fail to act “according to My commandment,” that will then lead to “strangers {non-Levites} shall enter this service of {the Levites},” and by extension, “there shall be wrath upon the Assembly of the Children of Israel.”
The explanation:
The central point of this section is “And you shall appoint the Levites over the Tabernacle of the Testimony... and they shall minister to it....” This verse establishes a command and injunction regarding the “separation” and “boundaries” that Hashem set up between the Levites and the regular Israelites. Through following these guidelines, we have the certainty that “strangers” will not enter the Tabernacle.
And this is why the Torah teaches us here that “The Children of Israel shall encamp, every man at his camp and every man at his division, according to their armies.” This is mentioned here not only to forestall and prevent “a stranger who approaches” (to prevent him from coming to perform the Levite service) but rather is its own independent command — to uphold the separation and boundaries within the Jewish nation.
Continuing in this vein, the Torah tells us, “The Levites shall encamp around the Tabernacle of the Testimony and there shall be no wrath upon the assembly of the Children of Israel”: The Torah continues to emphasize the importance of upholding the established boundaries (“The Children of Israel shall encamp, every man at his camp... The Levites shall encamp around the Tabernacle...”) through which they will be protected from there being “wrath.”
This is what Rashi is highlighting when he says, “If you will act according to My commandment — keeping the boundaries — there shall be no wrath.” And from the implication of the negative you infer the positive, that if there is a breakdown of these boundaries, there will be “wrath.” But this is only “wrath” in “potential.” Therefore, Rashi explains and emphasizes, “But if not, that strangers {non-Levites} shall enter this service of {the Levites}, there shall be wrath.” Only when the lack of boundaries leads to “strangers {non-Levites} shall enter...” in a literal sense will “there shall be wrath” in actuality.
