"Joshua drew not his hand back, wherewith he stretched out the spear, until he utterly destroyed all the inhabitants of Ai. ---Joshua 8:26.
"For this purpose the Son of God was manifested that he might destroy the works of the devil. --- 1 John 3:8.
A willing subjection to any one sin is not consistent with the grace of God, and true saving faith, Romans 6:14; for though wicked inhabitants will abide in the heart, and sometimes prevail over the believer, they must not reign there, nor should be suffered to stir without resistance: since we may be utterly ruined by the dominion of a single sin, that is, by a single subjection to it, as by the dominion of a thousand, just as a bird is caught by a single snare; and though you are actually converted, and have gained the dominion over your sins, yet you must not draw back your hand, and lay the spear and sword of the Spirit aside.
There is no truce in this war, nor any rest found, but in fighting; for if you beat not your enemies, they beat you. Therefore, the Christian soldier's watchtword is, Fight on, looking to Jesus. Satan left Christ only for a time; much more will he renew his assaults upon us again and again; nay, if a man is not watchful, but presumptuous, "he takes to him seven other spirits more wicked than himself." But if the conflict lasteth long, remember that is also the case of others; and even the ancient fathers have gone under it till they were gray; at last the victory will be the more sweet and glorious. Only, above all things, take the shield of faith, for faith alone triumphs; by which we are in covenant with Christ, and he makes one cause with us.
'Tis faith that conquers earth and hell,
By a celestial power;
This is the grace that shall prevail
In the decisive hour.