John Gill Commentary Ezekiel 45:14

"and the set portion of oil, of the bath of oil, the tenth part of a bath out of the cor, [which is] ten baths, even a homer; (for ten baths are a homer;)" — Ezekiel 45:14 (ASV)

Concerning the ordinance of oil, the bath of oil

This shows that the bath was for liquid measure; and as oil was a part of food with the Jews, as well as used in their offerings, a rule is given for the distribution of that to the Lord's ministers, that they may have everything convenient for them.

You shall offer the tenth part of a bath out of a cor; which was the same measure with the "homer", only another name for it, as follows: which is an homer of ten baths, for ten baths are an homer.

So that if a man had an homer or ten baths of oil, he was to give a hundredth part of it for the use of the priests and Levites, or ministers of the word; a greater portion of wheat or barley is given than of oil, because there is a greater expense in families of the one than of the other.