Augustine of Hippo

To be sure, we heard in that reading, "But when they deliver you up, do not be anxious how or what you are to speak … for it is not you who are speaking but the Spirit of your Father who speaks through you." And he says in another place: "Behold, I am with you always, even to the end of the world." Does this mean that the people who heard those words of the Lord would be here until the end of the world? …

Sermon 64A.2 ↗

Gregory the Dialogist

"For I will give you a mouth and wisdom, which all your adversaries will not be able to resist or contradict." As if He openly says to His weakening members: Do not be terrified, do not be afraid; you approach the contest, but I fight; you utter the words, but I am the one who speaks.

Forty Gospel Homilies, Homily 35 ↗

Thomas Aquinas

But who is the author? Certainly the Holy Spirit, for it is not you who speak, but the Spirit of your Father speaking through you. Something like this is expressed by Paul in 2 Corinthians (13:3): "Do you want proof that Christ is speaking in me?" But does not this make them seem possessed? It should be noted that every action proceeding from two causes, one of which is the principal actor and the second instrumental, should be named from the more principal. …

Commentary on Matthew ↗