There is a link between the last stanza (vv. 145-152) and these two stanzas (vv. 153-168). The enemies of the psalmist are still present, as they have been throughout the psalm, and he is still praying: “Deliver me” (v. 153), “defend my cause and redeem me” (v. 154), “renew my life” (vv. 154, 156), and “preserve my life" (v. 159). Derek Kidner says that there even seems to be “a mounting urgency” in these repeated pleas for salvation. At the same time, there is also a significant change as we move from the former stanza to these two. The last set of verses was almost entirely a prayer. In these stanzas the petitions tend to drop away—stanza twenty-one (the sin/shin stanza) has no explicit prayers at all—and in their place comes a quiet, obedient waiting upon God. 

The third thing the psalmist teaches about prayer in these verses is that prayer is best when it is biblical, that is, when it accompanies and flows from serious Bible study and when it is, in a sense, repeating God's very words, teaching, decrees and promises back to him. It is when our own prayer words become biblical. The psalmist expresses this when he talks about God hearing him “in accordance with your love” and renewing his life “according to your laws” (v. 149). What distresses him about the wicked is that “they are far from your law" (v. 150). 

The second New Testament passage we are going to look at is from the book of James. James has a lot to say about prayer, and toward the end of the book he picks up on this important theme again, saying that “the prayer of a righteous man is powerful and effective” (5:16). 

This is another reason why the psalmist knew that God's words are wonderful. It is because they are altogether righteous. Two thoughts go together in these references. First, the source of righteousness is the character of God (“Righteous are you, O LORD,” v. 137; "Your righteousness is everlasting,” v. 142). Second, the Law of God gives expression to that righteousness (“Your laws are right,” v. 137; “The statutes you have laid down are righteous,” v. 138; “Your statutes are forever right,” v. 144). A way we might express this is to say that the Bible mirrors the character of God. 

As we noted in yesterday's study, Luther made a strong point of indicating that the Word gives understanding “to the simple.” How this works is illustrated by the way Jesus dealt with the Emmaus disciples in the story recorded in Luke 24. These two people, probably Cleopas and his wife, Mary, were returning home after the crucifixion when Jesus drew near them on the road. They did not recognize him. When he asked why they were downcast they replied by telling him what had happened in Jerusalem at the time of the Passover.