Verses 1–7
NUMBERS - CHAPTER EIGHTEEN
Verses 1-7:
This is an unusual text, in that God spoke directly to Aaron. The usual method of instruction was, "The Lord spake unto Moses. . ." or " unto Moses and Aaron." In this instance, God addressed Aaron as the head of the priestly lineage.
"Thy father’s house," refers to the Kohathites, who had charge of the sanctuary and its sacred things.
"Bear the iniquity," from nasa and avon, "lift up and bear away the perversity," or to bear the responsibility for the iniquity. This defines the priests’ position as the intermediary between God and Israel. The sins of the people were not placed upon the priests; they bore the sins before God with the appropriate sacrifices necessary for atonement and redemption and cleansing. This position included the entire tribe of Levi.
The text is very precise in designating only the priests, descendants of Aaron, as those who were to officiate in the sacrificial offerings. The role of the Levites, other than Aaron’s sons, was to relieve the priests of the drudgery and routine of the Divine service, freeing the priests to devote their time to the sacrifices.
None of the Levites except Aaron’s sons the priests were to "come near" to the altar to offer sacrifice, nor to enter the sanctuary, under penalty of death.
Aaron and his sons were to regard the priestly office not as a duty but as a gift from the God of grace.
"Service," abodah, also translated "labor, ministry, office."
"Gift," mattanah, a thing bestowed upon one, not earned nor bought.
This illustrates the gifts of ministry and service God bestows upon His children today, Eph 4:11-16; Ro 12:6-8