Theophylact of Ohrid

You persecute Me under the pretext that you love God. But this is not so, no. For I know about you that you do not have the love of God in yourselves, even though you put forward everywhere that you persecute Me out of love for God. The Jews, indeed, did not have the love of God, because they persecuted self-existent Love — the Son of God. Indeed, they did not have His word abiding in them either, for they rejected the Word and God.

Commentary on John ↗

Thomas Aquinas

Thus Christ presented the various testimonies to himself not for the reason they thought, but for another one: because I know you, i.e., I have made known about you, that you do not have the love of God in your hearts, although you pretend to have it. And so you are not persecuting me because of your love for God. You would be persecuting me for the love of God if God and the Scriptures did not bear witness to me; but God himself bears witness to me by himself, his works and in the Scriptures, as has been said. …

Commentary on John ↗

Bonaventure

"But I know you, that you do not have the love of God in you," but rather hatred: below in chapter fifteen: "Now they have both seen and hated both me and my Father." And such people are worthy of rebuke, because they lack the wedding garment: Matthew twenty-two: "Friend, how did you come in here, not having a wedding garment?"

Commentary on John, Chapter 5 ↗