Charles Ellicott Commentary Numbers 18:22

"And henceforth the children of Israel shall not come nigh the tent of meeting, lest they bear sin, and die." — Numbers 18:22 (ASV)

Lest they bear sin and die.— that is, lest they bring sin upon themselves, the penalty of which they would have to bear. This appears to be the primary meaning of the phrase, from which the secondary meaning, namely, that of bearing sin in the sense of atoning for it, is derived. (Leviticus 22:9.)