John Chrysostom

"Do all things without murmurings and disputings." The devil, when he finds that he has no power to withdraw us from doing right, wishes to spoil our reward by other means. For he has taken occasion to insinuate pride or vainglory, or if none of these things, then murmuring, or, if not this, misgivings. Now then see how Paul sweeps away all these. …

Homily on Philippians 8 ↗

Theophylact of Ohrid

The devil, when he is unable to completely turn someone away from good, drives him either to despair or to vainglory; and if he cannot accomplish even this, he suggests to him murmuring or doubt and unbelief. Since the Philippians were subjected to temptations and constant dangers, as a result many of them fell into murmuring and blasphemy; therefore the apostle says: "do all things without murmuring." For whoever murmurs becomes ungrateful and abusive in speech. …

Commentary on Philippians ↗

Cyprian

That we must never murmur, but bless God concerning all things that happen. In Job: "Say some word against the Lord, and die. But he, looking upon her, said, Thou speakest as one of the foolish women. If we have received good things from the Lord's hand, why shall we not endure evil things? In all these things which happened unto him, Job sinned not with his lips in the sight of the Lord." Also in the same place: "Hast thou regarded my servant Job? …

Treatise XII. Three Books of Testimonies Against the Jews. ↗

Thomas Aquinas

Above, the Apostle exhorted them to do works leading to salvation; here he teaches them how. First, he teaches them the way to do these works; secondly, he gives the reason (2:15). First, he points out two ways to act, namely, without grumbling or questioning. For virtuous works are very difficult, and offer a fertile field for grumbling: "We must not grumble, as some of them did and were destroyed by the Destroyer" (1 Cor. 10:10). …

Commentary on Philippians ↗