I was blameless before Him, and I kept myself from my lawlessness.
The word “blameless” here has the sense of wholeness and sincerity, not absolute freedom from sin. David wants to say that before God he has not chosen a double life. The phrase “from my iniquity” is also noteworthy. A person often has particular weaknesses toward which he must show special watchfulness. David knows that faithfulness requires vigilance precisely in those places where the danger of stumbling is great. For the believer, this is practical wisdom. The general desire “not to sin” must be turned into specific watchfulness toward everyday temptations. Yet watchfulness does not mean trusting in one’s own strength. The previous verses show that the Lord is the One who keeps. We responsibly turn away from occasions for sin and at the same time rely on His grace. Holiness is not a claim to be flawless, but a course of living sincerely before God and, by His grace, remaining far from sin.