Psalmen 40:11

The psalmist, having meditated upon the work of redemption, and spoken of it in the person of the Messiah, now comes to make improvement of the doctrine of his mediation between us and God, and therefore speaks in his own person. Christ having done his Father's will, and finished his work, and given orders for the preaching of the gospel to every creature, we are encouraged to come boldly to the throne of grace, for mercy and grace. I. This may encourage us to pray for the mercy of God, and to put ourselves under the protection of that mercy, Psa 40:11. "Lord, thou hast not spared thy Son, nor withheld him; withhold not thou thy tender mercies then, which thou hast laid up for us in him; for wilt thou not with him also freely give us all things? Rom 8:32. Let thy lovingkindness and thy truth continually preserve me." The best saints are in continual danger, and see themselves undone if they be not continually preserved by the grace of God; and the everlasting lovingkindness and truth of God are what we have to depend upon for our preservation to the heavenly kingdom, Psa 61:7. II. This may encourage us in reference to the guilt of sin, that Jesus Christ has done that towards our discharge from it which sacrifice and offering could not do. See here, 1. The frightful sight he had of sin, Psa 40:12. This was it that made the discovery he was now favoured with of a Redeemer very welcome to him. He saw his iniquities to be evils, the worst of evils; he saw that they compassed him about; in all the reviews of his life, and his reflections upon each step of it, still he discovered something amiss. The threatening consequences of his sin surrounded him. Look which way he would, he saw some mischief or other waiting for him, which he was conscious to himself his sins had deserve…

40:11 The psalmist prays that the Lord will be true to his character when answering this plea for mercy.