Gregory the Great — on 1Cor 11:3 (Forty Gospel Homilies, Homily 33)

“"You did not anoint my head with oil." If we understand the feet of the Lord as the mystery of his incarnation, fittingly his divinity is designated by his head. Hence also through Paul it is said: "The head of Christ is God." For the Jewish people professed to believe in God, and not in him as if in a man. But it is said to the Pharisee, "You did not anoint my head with oil," because he neglected to proclaim with worthy praise even that very power of his divinity, in which the Jewish people pledged to believe.”