Parshat Tetzave concerns itself almost exclusively with the Kohanim (Priests). After stipulating that the Kohanim are defined as Aaron and his children, the Torah then introduces the special garments they wear when performing the service in the mishkan (tabernacle). Just as those who serve in a royal palace wear special uniforms, the Kohanim wear special vestments when they serve G-d in his royal palace, the mishkan.
The Kohen Gadol (High Priest) wore eight garments: The mitznefes (hat), tzitz (head plate), choshen (breastplate), efod (apron), me'il (blue coat), michnasayim (pants), avnet (sash) and ketones (shirt). All other Kohanim wore four garments: The migba'at (hat), ketonet (shirt), michnasayim (pants) and avnet (sash).
The Torah then discusses the seven days of the dedication service by which Aaron and his offspring would become priests. This week served as an orientation for Aaron and his children.
The final discussion of this week’s Torah portion relates to the daily sacrifice in the mishkan, the korban tomid, and the details of the second altar - the golden mizbe'ach.