29 For by you I can run against a troop,
and by my God I can leap over a wall . . .
34 He trains my hands for war,
so that my arms can bend a bow of bronze.
35 You have given me the shield of your salvation,
and your right hand supported me,
and your gentleness made me great.
36 You gave a wide place for my steps under me,
and my feet did not slip.
37 I pursued my enemies and overtook them,
and did not turn back till they were consumed.
Psalm 18:29, 34-37 (ESV)
It is common for the preacher to feel inadequate in the moments before he takes the pulpit to deliver his message. As the congregation sings gladly of “a mighty fortress” and “blessed assurance,” he rehearses his shortcomings and despairs of his ability to meet the challenge of faithful, effectual exposition. The text may be difficult, the audience cold, and the world hostile. The man of God may well be tempted to grieve, along with the great 18th century missionary, David Brainerd, for the congregation, “that they should sit there to hear such a dead dog as I preach.” But he need not feel so, for God can equip him to do battle.
The military imagery of Psalm 18 foreshadows the description, in Ephesians 6, of the “whole armor of God” available to the Christian. Both speak of mighty weapons, armor, and sure footing. Both enumerate essentials for the soldier of any era. Bronze has given way to titanium and Kevlar, sandals to treaded boots, and bows and swords to rifles and grenades, but the necessities of combat remain the same.
No sane civilian supposes that he can simply pick up a stick and run at the enemy. He needs training, equipping, and support every step of the way. The Psalmist rejoices that these benefits are ever available to him. And though preparation for war can be demanding, it is not debilitating; God’s “gentleness” makes the warrior great (v. 35). The Lord’s “boot camp” is rigorous, but manageable, and the recruit comes to recognize the wisdom of his trainer over the folly of the enemy.
Finally, it is not a game. The aim of all this exertion is destruction of the enemy (v. 37). God’s soldiers are not playing war, with “Bang. Bang. I got you”—“No you didn’t”—“Yes, I did.” When war is properly conducted, strongholds fall and foes retreat. On the spiritual battlefield, the same is true for anointed preaching. The enemy is real enough. Society and the Church are full of forces which threaten the life in the Spirit. Liars and fools have sacked the culture and are preying on the young and impressionable. Sermons are relatively undistinguished as is the preacher. What hope is there of victory?
Lest the man of God despair, he should savor the lesson of Psalm 18. When he preaches, God will enable him to leap walls of discouragement, confusion, and intimidation as he meets the devil’s schemes head on. He is fortified by the Holy Spirit and stands firmly on the Word of God. Providence surrounds him and his eternal destiny is secure. So when the singing and music end, he walks confidently to the pulpit, opens the Bible, and begins, “Thus saith the Lord.”
 Jonathan Edwards, The Life and Diary of David Brainerd, in The Works of Jonathan Edwards, vol. 2 (1834; reprint, Peabody, MA: Hendrickson Publishers, Inc. 2003), 330.
 Kevlar is the DuPont Company’s brand name for a particularly light but very strong synthetic fiber.