John Chrysostom

"And if a man also strive for masteries, yet is he not crowned except he strive lawfully." These things are said indeed to Timothy, but through him they are addressed to every teacher and disciple. Let no one therefore of those who hold the office of a Bishop disdain to hear these things, but let him be ashamed not to do them. "If any one strive for masteries," he says, "he is not crowned, except he strive lawfully." What is meant by "lawfully"? …

Homily on 2 Timothy 4 ↗

Theophylact of Ohrid

That is, it is not enough to enter the contest, or to anoint oneself, or to engage with an opponent, if a person does not observe the laws of wrestling concerning food, drink, abstinence, and the very manner of wrestling. For one is not left to compete however one wishes, but there are laws regarding this as well — laws of competition. Observe the wisdom of Paul. …

Commentary on 2 Timothy ↗

Oecumenius

And if anyone competes as an athlete, he is not crowned unless he competes according to the rules. unless he competes according to the rules. For it is not enough merely to be anointed, or to enter the place of combat, or to engage in hand-to-hand fighting with the enemy, but it is also necessary to endure and to win: for this is the law of combat.

Commentary On 2 Timothy ↗

Ambrose of Milan

What is the world but a sort of arena of continual strife? Wherefore also in the Apocalypse the Lord says, "To him that overcometh will I give a crown of life;" and Paul says, "I have fought a good fight;" and in another place, "No man is crowned except he strive lawfully." He who institutes this combat is Almighty God. …

Letter 43 ↗

Thomas Aquinas

He also who strives for the mastery is not crowned, except he strive lawfully. But because someone might say: you put heavy burdens on us, Paul; but what fruit do they bring? He answers: take as your example the battles of this world, where not all but only those who fight lawfully receive the crown. …

Commentary on 2 Timothy ↗