This time what has caught my attention is verse 117: "Hold me up, that I may be safe and have regard for Your statutes continually." It struck me that this verse encapsulates the distinction between the Reformed, biblical view of perseverance of the saints, in contrast to the unbiblical view of "once saved, always saved."
The first part could be taken either way. It uses the imperative, "Hold me up." Thus, this anonymous author demonstrates that he understands that the life of a believer doesn't arise within himself, but is something done by God in the believer. Then he expresses his belief that the holding up by God is what keeps a believer safe. This sounds a lot like the words of Jesus (John 10:27-29): "My sheep hear My voice, and I know them, and they follow Me. I give them eternal life, and they will never perish, and no one will snatch them out of My hand. My Father, who has given them to Me, is greater than all, and no one is able to snatch them out of the Father’s hand." It is not the believer's strength that keeps him spiritually safe, because he has none. It is all of God.
It is the last phrase that separates the biblical doctrine from its unbiblical rival. "Once saved, always saved" leaves the professing believer with his hand up, or signing a decision card, but then living like an unbeliever, thinking that he is safe because he made a profession. Instead, the Psalmist prays that "[I may] have regard for Your statutes continually." This is the difference with perseverance. The Calvinist knows that God doesn't preserve us in unbelief, but rather in new life. For the one with true faith, the Holy Spirit carries him through his life, striving for holiness, becoming more and more like the Jesus who bought him on the cross. Notice these words of Paul: "I am sure of this, that He who began a good work in you will bring it to completion at the day of Jesus Christ." What good work? "It is God who works in you, both to will and to work for His good pleasure" (Philippians 1:6, 2:13). Psalm 119:117 is the prayer of the believer that God would sustain him in faith and life. Philippians 1:6 and 2:13 are the fulfillment of that prayer!