John Chrysostom

As if He says, Think not that thy disciple needs you, but that you do not need him. For I who need no one whom all things in heaven and earth need, have condescended to the degree of a servant.

Catena Aurea by Aquinas ↗

Theophylact of Ohrid

Secondly, by His own example, for having explained that He serves them, He thereby leads them to humility. It was precisely at that time that He, as it is said, distributed to them the bread and the cup. If I, Whom all the angelic and rational creation worships, serve in your midst, then how do you dare to think highly of yourselves and argue about primacy? …

Commentary on Luke ↗

Bede

For who is greater, the one who reclines or the one who serves? Is it not the one who reclines? But I am among you as the one who serves. To his words of exhortation, he adds examples, which the evangelist John more fully records, writing among other things: If I, the Lord and Master, have washed your feet, you also ought to wash one another's feet (John XIII). Although by the word of serving, all the things that God did in the flesh can be understood. …

On the Gospel of Luke ↗

Bonaventure

Third, as regards the example urging humility, he adds: For which is greater, he who reclines at table, or he who serves? He asks this as something self-evident, and therefore responds: Is it not he who reclines at table? This is indeed true according to the order that is observed according to worldly custom and usage; whence above in the seventeenth chapter: "But which of you, having a servant, who when he returns from the field would say to him: Come over and recline at table; and not rather: Come and serve me?" But it is otherwise …

Commentary on Luke, Chapter 22 ↗