The twentieth psalm and the immediately following twenty-first psalm are different from the psalms we have studied thus far in that they were designed to be sung by the Jewish people on behalf of their king and nation. The first is a prayer for the king's victory in a day of battle. The second is a prayer of thanksgiving for that deliverance.
It is only after this evaluation that we find the completion of the parallel in a statement of two things the Scriptures do: "By them is your servant warned" and "in keeping of them there is great reward" (v. 11). In other words, because the words of God are sure and righteous, the servants of God are warned by them and the keepers of them are rewarded.
Being radiant, it gives light to the eyes. This combination of ideas is easy for us to understand, both on the literal and metaphorical levels. Literally, an object that is radiant or gives off light makes vision possible. The sun does it, as well as other sources of light, such as candles or lamps or, in our case, light bulbs, chandeliers or flashlights. Metaphorically, anything that illumines a right life path enables us to walk in it without stumbling. This is the idea here, though it probably also has the idea of purging darkness out of us and thus enabling us to see clearly and without distortion. Psalm 119:105 embraces these ideas when it says, "Your word is a lamp to my feet and a light for my path."
At first glance, a person might suppose that what I have said about the way David looked at the law is not very important, at least for us today. One might comment, "So what does it matter if David regarded the Scriptures as something to be obeyed rather than merely looking at them stylistically, as we do?" But what David said is not an unimportant matter, however, since what is said about the law in the second half of the psalm depends upon it. In other words, it is because the Bible is God's law, statutes, precepts, commands, fear and ordinances that it is perfect, trustworthy, right, radiant, pure and sure, which is what David says it is. And it is because it is like this that it can do the things David says it does do.
It would be hard to discover in all the Bible a more perfect example of Hebrew poetic parallelism than verses 7-9. There are six parallel statements in these verses, and each contains three elements which are likewise parallel. There are six terms for the written revelation, six adjectives to describe it, and six statements of what the Bible does.
