The Institutes, Book 5
The Apostle’s Many Contests
But when he says, “I run in such a way, not aimlessly,” he does not mean that he has finished only the contest of a race. That phrase has more particularly to do with the intention of his mind and the fervor of his spirit, in which he followed Christ with all eagerness, crying out with the Bride, “We will run after you, after the fragrance of your ointments,” and again, “My soul clings to you.” He also testifies that he has won in another kind of contest, when he says, “I fight in such a way, not as one who beats the air, but I discipline my body and bring it into subjection.” This properly has to do with the pains of abstinence, bodily fasting and the affliction of the flesh. By it he means that he is a vigorous boxer against his own flesh. He shows that he has not landed his blows of self-control on it in vain, but has won a battle and a triumph by putting his own body to death. For when the body is disciplined with the blows of self-control and struck down with the boxing gloves of fasting, he has secured for his victorious spirit the crown of immortality and the prize of incorruption.
You see the lawful method of the contest. Consider the outcome of spiritual combats: how the athlete of Christ, having won the victory over the rebellious flesh and cast it, as it were, under his feet, is carried forward in triumph on high. And so “he does not run aimlessly,” because he trusts that he will at once enter the holy city, the heavenly Jerusalem. He “fights in such a way,” that is, with fasts and the humbling of the flesh, “not as one who beats the air,” that is, striking into empty space with blows of self-control. Through these blows he struck, not the empty air, but the spirits who live in it, by disciplining his body. For one who says “not as one who beats the air” shows that he is striking, not empty and void air, but certain beings in the air. And because he had won in this kind of contest, and marched on enriched with the rewards of many crowns, he deservedly begins to enter the contest against still more powerful enemies. Having triumphed over his former rivals, he boldly proclaims, “Now our struggle is not against flesh and blood, but against principalities, against powers, against the world rulers of this darkness, against spiritual wickedness in the heavenly places.”