Numbers 3:10

ואת אהרן ואת בניו תפקד AND THOU SHALT CHARGE AARON AND HIS SONS — The word תפקד is an expression for “appointing” and not an expression for “counting” (although it is Kal, and usually “appointing” is expressed by the Hiphil of the verb; cf. Rashi on Numbers 1:50). ושמרו את כהנתם AND THEY SHALL KEEP THEIR PRIESTS OFFICE — the receiving of the blood in holy vessels, the sprinkling of it, the burning of the fat and the other rites which are entrusted to the priests’ charge.

And thou shalt appoint Aharon and his sons, and they shall keep their priest’s office: and the stranger that comes near shall be put to death.

וְאֶת־אַהֲרֹ֤ן וְאֶת־בָּנָיו֙ תִּפְקֹ֔ד וְשָׁמְר֖וּ אֶת־כְּהֻנָּתָ֑ם וְהַזָּ֥ר הַקָּרֵ֖ב יוּמָֽת׃ {פ}