Gregory the Great, on 1Sam 16:5

“And he said: It is peaceable: I am come to offer sacrifice to the Lord, be ye sanctified, and come with me to the sacrifice. And he sanctified Isai and his sons, and called them to the sacrifice.”

“27. What is it for a priest to sacrifice, except to join the hearts of the elect to our Redeemer through love? As if he were saying: You wish to know whether he has come, but it does not profit to be known unless it profits to be loved. I have come therefore to sacrifice to the Lord. Hence it is that Paul expels those in whom he could not sacrifice, saying: "If anyone does not love the Lord Jesus, let him be anathema" (1 Cor. 16:22). But to those invited to the sacrifice it is said: "Sanctify yourselves, and come." The Jews therefore cannot come with us to the sacrifice of faith, because they refuse to judge the Lord Jesus from the Scriptures, but out of hatred alone they flee from hearing his preaching. Whence the Lord complains through himself, saying: "If I had not done among them the works that no one else did, they would have no sin; but now they have no excuse, because they have seen and hated both me and my Father" (John 15:24). What then is the meaning of what is said: "Sanctify yourselves, and come"? But for hearers to be sanctified is to prepare the secret place of a pure mind for hearing. For them to be sanctified is indeed to cast hatred from the heart, and to prepare purity of intention for hearing the word of preaching. Therefore the sanctified are commanded to come, because coming profits nothing for those who do not have purity of intention in hearing. And because the Holy Spirit speaks through holy teachers, he says: "Come with me" — as if to say: Attend to the one speaking in such a way that you believe the one hearing is with you, because I speak in such a way that I hear, since I myself am the one who speaks and governs the speaking. And because at the beginning of the nascent Church many of the Jews both heard devoutly and believed faithfully, it is rightly said that Jesse and his sons were sanctified by Samuel and invited to the sacrifice.”

Imported from an open dataset — not yet checked against the printed edition.