Psalm 118 is by far the longest Psalm and the one most artificially constructed. It consists of twenty-two sections in alphabetical order with each of the eight verses in each section beginning with the same letter of the Hebrew alphabet. It focuses on Gods gift of his law, which is understood very broadly to include Gods teachings, commands, statements, etc., and multiplies responses of gratitude, commitment, and obedience on the part of the Psalmist. St. Augustines commentary on the Psalm focuses on two themes: the movement from merely external obedience to inward commitment of the heart and mind, which is often accompanied by a parallel movement from fear to love. Both themes appear in this extract:
"Set before me as a law the way of your justifications, Lord, and I will always seek after it (Ps 118, 34). The Apostle said, The law is not made for the just person, but for the unjust and disobedient, etc., at the end of which he says: And whatever other thing is contrary to sound doctrine, which is according to the gospel of the glory of the blessed God, which has been entrusted to me (1 Tim 1:9-11). Is the one who says, Set a law for me, Lord, the sort of person for whom Paul says that the law was made? Of course not! If he were that sort of person, he would not have said above, I have run the way of your commandments, when you broadened my heart (Ps 118, 33). What does it mean, then, that he prays that a law be set before him, if the law is not set for the just person? Perhaps it means that the law is not made for the just in the way in which it was set before the stubborn people, on stone tablets (Ex 31:18) and not on the fleshly tablets of the heart (2 Cor 3:3), that is, according to the old covenant from Mount Sion that generates unto slavery (Gal 4:24), and not according to the new covenant of which the prophet Jeremiah writes: Days are coming, says the Lord, and I will make a new covenant with the house of Israel and with the house of Judah, not according to the covenant which I made with their fathers on the day that I took them by the hand to bring them out of the land of Egypt. Because they did not remain in my covenant, and I neglected them, says the Lord. But this is the covenant that I will make with the house of Israel: After those days, says the Lord, I will give my laws in their minds and on their hearts I will write them (Jer 31:33-34). This is is how the Psalmist wishes a law to be set before him by the Lord: not as the law was given to the unjust and disobedient, belonging to the old covenant, on stone tablets, but as it is given to the holy children of the free, that is, the holy Jerusalem above (see Gal 4:26), to the children of the promise, to the children of an eternal inheritance, given to the mind by Gods finger, and written on hearts. Not the law that people keep in memory and neglect in their lives, but the law that they know by understanding and do by loving, in the breadth of love and not in the narrowness of fear. One who does what the law requires out of fear and not out of love of righteousness, does it unwillingly. What he does unwillingly, he would prefer, if possible, that it not be commanded; he is not a friend but an enemy of a law that he wishes didnt exist; and one whose will is thus unclean is not cleansed by what he does. Such a person cannot say what the Psalmist says in the previous verse: I have run the way of your commandments when you broadened my heart. This broadening refers to charity which according to the Apostle is the fulfilment of the law (Rom 13:10). [Augustine, En. in Ps 1181; PL 37, 1528]
I was struck by the similarity of these paragraphs to the interpretation of verse 33 in John Goldingays commentary (Vol III, p. 396):
Usually we simply walk in the way... of Yhwhs commands (vv. 1-4); running in the way of them is another way of suggesting not mere compliance with Yhwhs expectations but living by them enthusiastically and energetically.... Suggestively, such running issues from having ones mind or heart broadened. That has a positive connotation, as in Is 60:5 (contrast Ps 101:5). There as elsewhere broadening is an image for deliverance; we are taken out of constraint into roominess (cf. 118:5). In this case mind and heart are perhaps being liberated from anxiety and fear. The logic is once again that Yhwhs act of deliverance liberates us into a life of obedience.
The paradox of that last line bears consideration.