וְאֶל־הַלְוִיִּ֣ם תְּדַבֵּר֮ וְאָמַרְתָּ֣ אֲלֵהֶם֒ כִּֽי־תִ֠קְחוּ מֵאֵ֨ת בְּנֵֽי־יִשְׂרָאֵ֜ל אֶת־הַֽמַּעֲשֵׂ֗ר אֲשֶׁ֨ר נָתַ֧תִּי לָכֶ֛ם מֵאִתָּ֖ם בְּנַחֲלַתְכֶ֑ם וַהֲרֵמֹתֶ֤ם מִמֶּ֙נּוּ֙ תְּרוּמַ֣ת יְהוָ֔ה מַעֲשֵׂ֖ר מִן־הַֽמַּעֲשֵֽׂר׃
“At sa mga Levita ay magsasalita ka at sasabihin mo sa kanila: Kapag kinuha ninyo mula sa mga anak ni Israel ang ikapu na ibinigay Ko sa inyo mula sa kanila bilang inyong mana, magbubukod kayo mula roon ng handog para sa Walang-Hanggan, isang ikapu mula sa ikapu.
Zohar
AND THE LORD SAID UNTO MOSES, SPEAK UNTO THE PRIESTS THE SONS OF AARON AND SAY UNTO THEM, THERE SHALL NONE DEFILE HIMSELF FOR THE DEAD AMONG HIS PEOPLE. R. Jose said: ‘What is the connection of this with the verse that immediately precedes, “A man also or a woman that hath a familiar spirit or that is a wizard shall be put to death” (Lev. 20, 27)? It is this: that having admonished the Israelites to sanctify themselves, the Scripture now admonishes the priests to sanctify themselves specially. Later, too, it admonishes the Levites (Num. 18, 21 et seq.), so that all should become holy and pure.
Sha'arei Orah
Our rabbis, of blessed memory, found it necessary to awaken us to this, and therefore informed us of a very important principle when they said,8Talmud Berachot 58a “The earthly kingdom is similar to the heavenly kingdom.” That is, if it is necessary to be careful about all the above matters when entering into the presence of an earthly king of flesh and blood, how much more is this so of a person who enters to greet the face of the King, King of kings, the Holy One, blessed is He, He Who is blessed and exalted.
Sha'arei Orah
It therefore states,40Numbers 18:25-26 “HaShem-יהו"ה spoke to Moshe saying, ‘Speak to the Levites and say to them, when you take from the children of Israel the tithe that I gave to you from them as your inheritance, separate a gift-offering to HaShem-יהו"ה, a tithe of a tithe.” The secret of the tithe of a tithe is the secret of אי"ק-1, 10, 100. That is, if the one-hundred are lacking, the ten are lacking, and if the ten are lacking, the one is lacking.