Numbers 18:1

“And the Lord spake unto Aaron, etc.] As the things spoken were such as concerned Aaron, he might be only and immediately spoken unto: thou, and thy sons, and thy father’s house with thee; meaning both priests and Levites, the priests by him and his sons, and the Levites by his father’s house: shall bear the iniquity of the sanctuary; the blame of any evil committed there, the punishment of it; the priests, Aaron and his sons, if they did not perform the duty of their office aright, he in the most holy place, and they in the holy place, and at the altar of burnt offering in the court; and the Levites, if they did not take care to watch in the tabernacle, and keep out strangers and polluted…”

“THE CHARGE OF THE PRIESTS AND LEVITES. (Num 18:1-7) the Lord said unto Aaron, Thou and thy sons and thy father's house with thee shall bear the iniquity of the sanctuary--Security is here given to the people from the fears expressed (Num 17:12), by the responsibility of attending to all sacred things being devolved upon the priesthood, together with the penalties incurred through neglect; and thus the solemn responsibilities annexed to their high dignity, of having to answer not only for their own sins, but also for the sins of the people, were calculated in a great measure to remove all feeling of envy at the elevation of Aaron's family, when the honor was weighed in the balance with its…”

“The iniquity of the sanctuary - i. e. the guilt of the offences which an erring people would be continually committing against the majesty of God, when brought into contact, through the ordinances, with the manifestations of His presence. Compare the marginal reference. The iniquity of your priesthood - As the priests themselves were but men, they were strengthened to bear the iniquity of their own unintentional offences, by being entrusted with the ceremonial means of taking it away (compare Leviticus 16:0). The word “bear” has, in the Old Testament, this double sense of “enduring” and “removing;” but in the person of Christ, who atoned by His own endurance, the two axe in effect one.…”

“Shall bear the iniquity of the sanctuary - Shall suffer the punishment of all the usurpations, or pollutions of the sanctuary, or the holy things, by the Levites, or any of the people, because you have power from me to keep them all within their bounds. Thus the people are in good measure secured against their fears. Also they are informed that Aaron's high dignity was attended with great burdens, having not only his own, but the people's sins to answer for; and therefore they had no such reason to envy him, if the benefits and dangers were equally considered. The iniquity of your priesthood - That is, Of all the errors committed by yourselves, or by you permitted in others in things,…”

“18:1-32 The instructions given here arose from the need demonstrated in ch 17 for clear boundaries between the people and the priests and Levites. The distinctive privileges of the Levites were matched by significant responsibilities. One very important aspect of their work was to safeguard the Tabernacle from unauthorized entry (ch 16). 18:1-4 The Lord gave special authority to Aaron, his sons (the priests), and his relatives (the Levites), all of whom were held responsible for offenses against the sanctuary. But the priests alone were held responsible for their own violations of God’s instructions for their service.”

“Thou: Num 17:3, Num 17:7, Num 17:13; Heb 4:15 shall bear: To counterbalance the high honour conferred on Aaron and his family, and to allay the fears and abate the envy of the people, it is here declared, that the priest must bear the blame of everything which was not properly conducted in the sanctuary. Num 18:22, Num 14:34; Exo 28:38; Lev 22:9; Isa 53:6, Isa 53:11; Eze 3:18, Eze 3:19; Act 20:26, Act 20:27; Heb 13:17; Pe1 2:24 Numbers 18:2”

“The Official Duties and Rights of the Priests and Levites. - Num 18:1. To impress upon the minds of the priests and Levites the holiness and responsibility of their office, the service of Aaron, of his sons, and of his father's house, i.e., of the family of the Kohathites, is described as "bearing the iniquity of the sanctuary," and the service which was peculiar to the Aaronides, as "bearing the iniquity of their priesthood." "To bear the iniquity of the sanctuary" signifies not only "to have to make expiation for all that offended against the laws of the priests and the holy things, i.e., the desecration of these" (Knobel), but "iniquity or transgression at the sanctuary," i.e., the…”