Theme: Their Rock and Our Rock
In this week’s lessons we consider different reasons for which David offers thanksgiving as he reflects on God’s grace and faithfulness towards him.
Scripture: Psalm 18:1-24
Since this psalm is supposed to have been written late in David’s life as a summary of God’s repeated deliverances of him, these words immediately raise a question of how David could say this in light of his sin with Bathsheba and against her husband Uriah. How could he claim to have been “blameless” and to have “kept himself from sin” in view of this sad episode?
It is a good question, but the answer is probably to be seen in the next verses, which we will consider more fully in the second study of this psalm. In those verses David broadens what he says about himself in verses 20-24 to express the principle that God honors righteousness and judges sin even in this life. This is not a promise that the righteous will always prosper in all ways at all times. Some suffer the experience of Job. It does not even mean that there is anyone who ever does right all the time. But as a general principle, when we live for God and try to go in his way, he cares for us and blesses us. But when we go our own way, we bring misery and destruction on ourselves. This is all David is saying. If we were to remind him of his sin with Bathsheba, he would claim it as a proof of this principle since he suffered in a variety of ways as a consequence of that great sin. But even though that happened, just as similar transgressions are committed by us all, on the whole he was nevertheless a man after God’s own heart and was greatly blessed by God. He tried to serve God, and God was faithful to him throughout his long and prosperous rule over Israel.
There is more to this psalm, as I have been suggesting—an important second half, which we will look at in the next study. But I want to end this chapter with a different observation.
One of the great sermons of the American evangelist D. L. Moody was on God being our rock, though it was not based on Psalm 18 but on Deuteronomy 32:31, which in the version used by Moody read, “For their rock is not as our rock, even our enemies themselves being judges” (KJV). What caught Moody’s imagination was the second part of that verse: “even our enemies themselves being judges.” For he argued that in times of trouble the objects trusted by unbelievers fail them, and they concede that they do not find the help in their gods that Christians find in ours. Moody pursued this by talking about atheists, pantheists and infidels, claiming that in the hour of their death they do not turn to their atheism or pantheistic philosophy but rather, if they turn to anything at all, they ask a minister to pray for them. “I have never heard of an infidel going down to his grave happily,” claimed Moody. They have nothing to hang on to. “Their rock is not as our rock,” and they confess it.5
How different it is for Christians! We do not live perfect lives, and we stumble many times, sometimes dreadfully. But when we come to the end of life and look back on it, as David has done in this psalm, we confess that whatever our failings may have been, our God has not failed us. We confess as a true saying: “If we are faithless, he will remain faithful, for he cannot disown himself” (2 Tim. 2:13). There is no rock like our rock. Praise to the rock of our salvation!
Study Questions:

Why is David able to say that he is “blameless” and has “kept himself from sin” when we know that he has committed sins?
What is meant by the statement, “For their rock is not as our rock” (Deut. 32:31)?

Application: Sometimes we genuinely believe we are blameless when in fact there is something in our life that needs to change. Pray and ask the Lord for the Holy Spirit to make you increasingly sensitive to spiritual things and to be able to recognize areas in which you need to grow closer to the Lord Jesus Christ.
For Further Study: To see how Christ is our unfailing rock, download for free and listen to Donald Barnhouse’s message, “Christ, Rock in the Desert.”  (Discount will be applied at checkout.) 
5D. L. Moody, “Their Rock Is Not as Our Rock,” in Great Pulpit Masters, vol. 1, Dwight L. Moody (New York: Revell, 1949), pp. 47-58.

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