In the Treasury of David, C.H. Spurgeon comments
Here is David’s declaration and confession of faith, coupled with a testimony from his experience. The Lord is my strength. The Lord employs his power on our behalf, and moreover, infuses strength into us in our weakness. The psalmist, by an act of appropriating faith, takes the omnipotence of Jehovah to be his own. Dependence upon the invisible God gives great independence of spirit, inspiring us with confidence more than human. And my shield. Thus David found both sword and shield in his God. The Lord preserves his people from unnumbered ills; and the Christian warrior, sheltered behind his God, is far more safe than the hero when covered with his shield of brass or triple steel. My heart trusted in him, and I am helped. Heart work is sure work; heart trust is never disappointed. Faith must come before help, but help will never be long behindhand. Every day the believer may say, “I am helped, “for the divine assistance is vouchsafed us every moment, or we should go back unto perdition; when more manifest help is needed, we have but to put faith into exercise, and it will be given us. Therefore my heart greatly rejoiceth; and with my song will I praise him. The heart is mentioned twice to show the truth of his faith and his joy. Observe the adverb “greatly, “we need not be afraid of being too full of rejoicing at the remembrance of grace received. We serve a great God, let us greatly rejoice in him. A song is the soul’s fittest method of giving vent to its happiness, it were well if we were more like the singing lark, and less like the croaking raven. When the heart is glowing, the lips should not be silent. When God blesses us, we should bless him with all our heart.
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