St. Prosper of Aquitaine ca. 390-455
Like ointment on the head, which ran down upon the beard, upon the beard of Aaron…(Ps. 133.2) By the priest Aaron, that Priest is indicated who alone fulfills the sacrament of the true High Priest, not with a victim of another kind, but in the oblation of His own body and blood: same Priest, same Victim, Propitiator and Propitiation, the One who effects all the mysteries for which He was announced. Who died, was buried, and rose again, He ascended into heaven, exalting human nature above every other name, and sending the Holy Spirit, whose unction would penetrate every Church. (Explanation of the Psalms)