The role of the priest in ancient Israel was a sacred and multifaceted office, central to the spiritual and communal life of the nation. The duties of the priests were primarily outlined in the Pentateuch, particularly in the books of Exodus, Leviticus, Numbers, and Deuteronomy. These duties encompassed a wide range of responsibilities, including conducting sacrifices, maintaining the sanctuary, teaching the law, and serving as intermediaries between God and the people.

1. Conducting Sacrifices and Offerings

One of the primary duties of the priests was to perform the various sacrifices and offerings prescribed by the Mosaic Law. These included burnt offerings, grain offerings, peace offerings, sin offerings, and guilt offerings. The priests were responsible for ensuring that these sacrifices were conducted according to the specific regulations given by God. Leviticus 1:5-9 describes the process of the burnt offering: "Then he shall slaughter the young bull before the LORD, and Aaron’s sons the priests shall present the blood and sprinkle it on all sides of the altar at the entrance to the Tent of Meeting."

2. Maintaining the Sanctuary

The priests were charged with the care and maintenance of the Tabernacle, and later the Temple, which were the central places of worship for the Israelites. This included ensuring the sanctity and cleanliness of the holy place, as well as the proper handling and care of sacred objects. Numbers 18:5 states, "You are to perform the duties of the sanctuary and of the altar, so that wrath may not fall on the Israelites again."

3. Teaching the Law

Priests also held the responsibility of teaching the Israelites the statutes and commandments of God. They were to instruct the people in the ways of the Lord and ensure that the law was understood and followed. In Malachi 2:7 , it is written, "For the lips of a priest should preserve knowledge, and people should seek instruction from his mouth, because he is the messenger of the LORD of Hosts."

4. Serving as Intermediaries

As intermediaries between God and the people, priests played a crucial role in the spiritual life of Israel. They were to offer prayers and intercessions on behalf of the people and seek atonement for their sins. The high priest, in particular, had the unique duty of entering the Holy of Holies once a year on the Day of Atonement to make atonement for the sins of the nation (Leviticus 16:32-34).

5. Judging and Deciding Legal Matters

In addition to their religious duties, priests were sometimes called upon to judge and decide legal matters, particularly those involving ritual purity and other religious concerns. Deuteronomy 17:9 instructs, "Go to the Levitical priests and to the judge who is in office at that time. Inquire of them, and they will give you the verdict."

6. Blessing the People

The priests were also tasked with blessing the people in the name of the Lord. This was a significant aspect of their ministry, as it conveyed God's favor and peace upon the Israelites. The priestly blessing is recorded in Numbers 6:24-26 : "The LORD bless you and keep you; the LORD make His face shine upon you and be gracious to you; the LORD lift up His countenance upon you and give you peace."

The duties of the priests were integral to the covenant relationship between God and Israel, serving to maintain the holiness and order of the community. Through their service, the priests facilitated the worship and obedience of the people, ensuring that the nation remained in right standing with God.