Charles Ellicott Commentary Leviticus 21:11

"neither shall he go in to any dead body, nor defile himself for his father, or for his mother;" — Leviticus 21:11 (ASV)

Neither shall he go in to any dead body. Not only is he to abstain from showing sorrow for the troubles that happened to the community, or those whom he loves, but in the case of death he is not to enter a tent, house, or place where a human corpse was lying (Numbers 19:14), so that he would not contract defilement. According to the administrators of the Law during the second Temple, the expression any dead body extends to any part of it, so that if the high priest entered a place where a certain amount of blood from a dead body was found, he became defiled. Accordingly, “any dead soul,” which is the literal meaning of the phrase translated here as “dead body,” denotes the blood that constitutes the soul or life .

Nor defile himself for his father... A better rendering is, not for his father ... shall he defile himself, or, not even for his father, etc. Since the rigorous rule in the preceding clause already establishes the difference between the high priest and the ordinary priest, this clause simply offers an instance to illustrate it. While the ordinary priest was not only permitted, but even required, to attend the funeral ceremonies of at least seven of his relatives , the high priest was not even allowed to join in the funeral rites of his parents. The only exception made in his case was if he found a human body in an isolated place. In such circumstances, he was not only permitted, but it was a meritorious act on his part, to bury it .