The principal fight of the Christian is with the world, the flesh, and the devil. These are his never-dying foes. These are the three chief enemies against whom he must wage war. Unless he gets the victory over these three, all other victories are useless and vain.
The true Christian is called to be a soldier, and must behave as such from the day of his conversion to the day of his death, he is not meant to live a life of religious ease, indolence, and security, He must never imagine for a moment that he can sleep and dose along the way to heaven, like one travelling in an easy carriage. If he takes his standard of Christianity from the children of this world he may be content with such notions, but he will find no countenance for them in the Word of God. If the Bible is the rule of his faith and practice, he will find his lines laid down very plainly in this matter. He must “fight.”
With whom is the Christian soldier meant to fight? Not with other Christians. Wretched indeed is that man’s idea of religion who fancies that it consists in perpetual controversy. He who is never satisfied unless he is engaged in some strife between church and church, chapel and chapel, sect and sect, party and party, knows nothing yet as he ought to know. Never is the cause of sin so helped as when Christians waste their strength in quarreling with one another, and spend their time in petty squabbles.
No, indeed! The principal fight of the Christian is with the world, the flesh, and the devil. These are his never-dying foes. These are the three chief enemies against whom he must wage war. Unless he gets the victory over these three, all other victories are useless and vain. If he had a nature like an angel, and was not a fallen creature, the warfare would not be so essential. But with a corrupt heart, a busy devil, and an ensnaring world, he must either “fight” or be lost.
He must fight the flesh.
Even after conversion he carries within him a nature prone to evil, and a heart weak and unstable as water. To keep that heart from going astray, there is need of a daily struggle and a daily wrestling in prayer. “I keep under my body,” cries St. Paul, “and bring it into subjection.” “I see a law in my members warring against the law of my mind, and bringing me into captivity.” “O wretched man that I am, who shall deliver me from the body of this death? .… They that are Christ’s have crucified the flesh with the affections and lusts.” “Mortify your members which are upon the earth” (1 Cor. ix. 27; Rom. vii. 23, 24; Gal. v. 24; Coloss. iii. 5).