John Chrysostom

"And seeing one of them suffer wrong, he defended him, and avenged him that was oppressed, and smote the Egyptian: for he supposed his brethren would have understood how that God by his hand would deliver them: but they understood not." See how up to this point he is not yet offensive to them; how they listened to him while he said all this. And "his face," we read, "was as the face of an angel." "For he supposed," etc. And yet it was by deeds that his championship was shown; what intelligence was there need of here? …

Homily on Acts 16 ↗

Theophylact of Ohrid

"Having struck down the Egyptian," Moses avenged the one being oppressed by him. He did not kill the Egyptian out of frenzy or anger, but out of zeal for God. And that which is done out of zeal for God, even if it be killing, is not murder. Here is what Moses heard from the Lord concerning Phinehas, who killed two with one hand: "Phinehas… took a spear in his hand. And he went after the Israelite into the tent, and thrust both of them through… and the plague was stayed from the children of Israel" (Num. 25:7–8). …

Commentary on Acts ↗

Oecumenius

For the Savior, seeing that those from Israel endured covetousness terribly (for Satan leapt upon them as though crushing them), had mercy and intended to free them. Having somehow killed the one destined to do wrong, he hid him in the earth, that is, he shut him up among the underworld into Hades. Therefore, having pre-locked Satan as it were into Hades, the Savior appeared as the champion of justice to those from Israel. …

Commentary on Acts ↗