Theophylact of Ohrid

By the expression "having been exalted," David indicated the ascension and that He (Jesus) is in the heavens, but even this was not clear at first. Look: at the beginning of his speech, when he also brought the prophet Joel as a witness, he did not say that Christ sent the Holy Spirit, but said that the Father sent Him. …

Commentary on Acts ↗

Oecumenius

And again Peter ascribes the event to the Father. For he knows that this will draw on the listeners. Having spoken, "Having been exalted," and having approached the matter of the ascension, and that he is in the heavens. Therefore he did not speak plainly, saying that he is in the heavens. Since he proceeded so far, and remembered his signs and the resurrection, he next introduces, "He has poured out." For at first he was saying that this had been promised not about Christ but through Joel the prophet. …

Commentary on Acts ↗

Augustine of Hippo

Therefore also the Lord Jesus Christ Himself not only gave the Holy Spirit as God, but also received it as man, and therefore He is said to be full of grace, and of the Holy Spirit. And in the Acts of the Apostles it is more plainly written of Him, "Because God anointed Him with the Holy Spirit." Certainly not with visible oil but with the gift of grace which is signified by the visible ointment wherewith the Church anoints the baptized. …

On The Trinity, Book 15 ↗

Bede

And having received the promise of the Holy Spirit from the Father, He has poured out this which you see and hear. In Greek it is translated thus: He has poured out this gift which you now see and hear. Indeed, concerning Jesus, whom the Jews crucified and whom God raised, He taught that He is the Christ; but now gradually leading the listeners to higher belief, He signifies that this is the true God, by confirming that He has poured out the gift of the Holy Spirit, which any wise person recognizes to be of divine power alone. …

Retractions on Acts ↗

Victorinus of Pettau

"And He had in His right hand seven stars." He said that in His right hand He had seven stars, because the Holy Spirit of sevenfold agency was given into His power by the Father. As Peter exclaimed to the Jews: "Being at the right hand of God exalted, He hath shed forth this Spirit received from the Father, which ye both see and hear." Moreover, John the Baptist had also anticipated this, by saying to his disciples: "For God giveth not the Spirit by measure unto Him. …

Victorinus Commentary on the Apocalypse of the Blessed John ↗