The Mitzvah of sanctifying the Kohen

The commandment to sanctify the progeny of Ahron (Hebrew "מצוות קידוש זרעו של אהרן") is a commandment based in the Hebrew Bible, and developed in rabbinical teaching that requires believers in Judaism to sanctify their priests (kohanim) in various ways. These include assisting him to abstain from any prohibitions in the Law that apply to him, and by affording him first rights in areas relating to holiness and the service of God. In the enumeration of Maimonides this is the 32nd positive commandment of the Law.

In Hebrew the commandment is literally known as the mitzvah of sanctifying the "seed of Aaron" (Hebrew מצוות קידוש זרעו של אהרן).

At the time of the Jewish Exodus from Egypt, the sacrificial activity of the Jewish nation was conducted by the firstborn of Israel. After the sin of the Golden calf, God recounted the privilege of priesthood from the firstborn and gave it to Aaron, and his sons, as an everlasting priestly covenant.

Generally, the duties of Kehuna are not restricted to sacrificial offerings alone but include various other forms of service to the nation of Israel. These forms of service include Torah instruction (Leviticus 10:10-11, Ezekiel 44:23-24) and managing tzaraath(mildew and skin disease).

Along with the commandment that God commanded Moses to confer the priesthood to Aaron came along the commandment which involves the participation of the nation of Israel in maintaining and creating a state of holiness and sanctification of their priests. Examples of this sanctification include assisting the priest in abstaining from forbidden marriages, to maintain a general state of purity, and to furnish the priest with gifts (later in rabbinical enumeration counted as twenty-four priestly gifts) to carry out his required duties.

The inauguration of Aaron and his sons to perform the holy service in the tabernacle is related in Exodus and Leviticus:

According to the Sifsei Kohen to the Chumash since the priest or kohen is chosen by God to perform direct service to God, doing acts of sanctification to and honoring the Kohen demonstrate the sanctification of God himself in a practical setting. In a somewhat radical explanation Abraham ibn Ezra contends that the personality traits of the priest, given to him by God, are superior to those of the rest of the nation of Israel. Hence, the power to administer the priestly blessing and to be successful at prayer rests with the Kohen, thereby justifying preferential treatment from amongst the nation.

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