Leviticus 21:10-15

It was inappropriate for the high priest to uncover his head in mourning since the holy oil had anointed it. He was not to tear his clothes either (cf. Matthew 26:65). He could not marry a widow or a foreigner, as the other priests could. He was not to abandon his duties to conduct other business temporarily. He was not to "profane his offspring" (Leviticus 21:15) by marrying someone unsuitable to his position before God.