so that he does not defile his offspring among his people, for I am the LORD who sanctifies him.”
More was expected from a priest than from other people, but more from the high priest than from other priests, because upon his head the anointing oil was poured, and he was consecrated to put on the garments (Lev 21:10), both which were typical of the anointing and adorning of the Lord Jesus, with all the gifts and graces of the Holy Spirit, which he received without measure.
Commenting on Leviticus 21:10-15
Neither shall he profane his seed among his people,.... By marrying any such persons, whereby his children, born of them, would lie under disgrace, and be unfit to succeed him in the priesthood, or by marrying among mean persons, or by marrying them to such as were unlawful, and would be a disparagement to them: for I the Lord do sanctify him; separate him from...
Neither shall he profane his seed among his people: for I the LORD do sanctify him. (l) By marrying any unchaste or defamed woman.