Gradual Conquest

"I will not drive them out in a single year, because the land would become desolate and the wild beasts too numerous for you. Little by little I will drive them out before you, until you have increased enough to take possession of the land." (Exo. 23:29, 30). Thus it is with the children of God. If they had not enemies without and within, and oppositions in their way, there are some dangerous "beasts" that would be ready to "increase" upon them.

For instance, there is a beast which is called pride, which might grow upon you if you had no enemies to fight with. Hence, a thorn in the flesh was given to Paul that he might not be exalted above measure. Is not the thorn in the flesh well ordered, which prevents confidence in the flesh?

There is a beast called carnal security, which might grow upon you. But now there are enemies on all hands of you, to prevent your falling asleep, to keep you watching and waking, and constantly on your guard.

There is a beast called presumption, which might grow upon you, and make you think you were able to go forward to Heaven upon your own legs and in your own strength, if you found no such enemies in the way.

There is another beast called worldly-mindedness, which might grow upon you, if you had no adversaries and adversities to vex you, and wean you from the world. You would be in danger of saying, "It is good to be here." But now the wars and battles in your way to Heaven make you say with your heart, O! it is better to be there.

There is a beast, a filthy brute beast, called sensuality, which might grow upon you, believer, that might make you lukewarm and formal in all your duties, as well as carnal and light in the intervals of duties. But the sight of your spiritual enemies on the field will make you see a need to be spiritual, zealous, earnest, and fervent in spirit, serving the Lord.

There is also a filthy dumb beast which is called forgetfulness, which would certainly grow upon you, and be very dangerous to your soul and spiritual welfare, if your enemies were all destroyed. Therefore God says, "Slay them not, lest My people forget" (Psalm 59:11). If the execution were quick and hasty, the impressions of it would not be deep and durable. Swift destructions startle men for the present—but they are soon forgotten; therefore, when we think that God's judgments upon the nations of our spiritual enemies come on but very slowly, we must conclude that God has wise and holy ends in that gradual procedure. "Slay them not, lest My people forget."
—extract from a sermon by Ralph Erskine, 1760.

Yes, Christian reader, God has a good reason for permitting the lusts of the flesh to rage, at times, within you. All His ways are marked by infinite wisdom, even though very often we are unable to discern it. So it is here. How often has a saint bewildered why God has withheld that victory over indwelling sin, for which he has prayed so long and so earnestly.

There is a needs-be for failure—as well as victory; for sorrow—as well as joy. In the dust before Him is our proper place, and if we leave it, He allows us to be tripped up by Satan, to fling us back there! Moreover, as Mr. Erskine points out, our graces must be exercised if our "enemies" are to be prevented from having dominion over us. One day we shall perceive more clearly why God permitted us to experience so many falls, and to "go halting" all our days; and why it was that "little by little" He vanquished our spiritual foes.
Arthur Pink, 1936