Notes on the Bible, by Albert Barnes, [1834], at sacred-texts.com
The sense seems to be that, owing to his position in the nation, the priest is not to defile himself in any cases except those named in Lev 21:2-3. The Septuagint appear to have followed a different reading of the text which would mean, "he shall not defile himself for a moment." The explanation in the margin of our version is hardly in keeping with the prohibition to Ezekiel on a special occasion. See Eze 24:16.
These prohibitions given to the people at large (compare the margin reference.) had a special fitness for the Hebrew priests. They were the instruments of the divine will for averting death, all their sacrifices were a type of the death of Christ, which swallowed up death in victory Co1 15:54-57, and it would therefore have been unsuitable that they should have the same freedom as other people to become mourners.
The word here and in Lev 21:8 rendered "bread", is the same as is rendered food in Lev 3:11, Lev 3:16, etc., and meat in Lev 22:11. The reader of the English Bible should keep in view that bread, meat, and food, were nearly equivalent terms when our translation was made, and represent no distinctions that exist in the Hebrew.
Profane - A woman who has been seduced, or one of illegitimate birth. A somewhat stricter rule for the priests' marriages was revealed to the prophet in later times, Eze 44:22.
The people of Israel are now addressed. They are commanded to regard the priests, who perform for them the service of the altar, as holy in respect of their office.
burnt with fire - See the Lev 20:14 note.
It was the distinguishing mark of the anointing of the high priest, that the holy oil was poured upon his head like a crown (compare Lev 8:12).
Uncover his head - Rather, let his hair be disheveled. See the note at Lev 10:6.
Go out of the sanctuary - i. e. not for the purpose to which reference is here made. The words do not mean, as some have imagined, that his abode was confined to the sanctuary.
Profane his seed - i. e. by a marriage which was not in keeping with the holiness of his office.
He was not treated as an outcast, but enjoyed his privileges as a son of Aaron, except in regard to active duties.
A dwarf - One who is small and wasted, either short, as in the text, or slender, as in the margin. It is hardly likely that dwarfishness would be overlooked in this enumeration. So most critical authorities.
Scurry or scabbed - These words most probably include all affected with any skin disease.
See Lev 2:3 note; Lev 6:25 note.
Sanctuaries - The places especially holy, including the most holy place, the holy place, and the altar.
This law is of course to be regarded as one development of the great principle that all which is devoted to the service of God should be as perfect as possible of its kind.