The worst thing in life is not to have some evil thing done against you. The worst thing in life is when you are the one that does the evil. The greatest peace possible in this life does not come from being invulnerable to external evil but knowing that you yourself have been delivered from internal evil. David here reminds himself of this fact. He is being tormented by evil adversaries from without but he draws consolation from the fact that while he may suffer from their evil yet he will not suffer from having shared in it. His innocence is his greatest possession. And this cannot be taken away. He knows he is cherished by God, the apple of God’s eye. Therefore, even in the face of external threat, he is able to hide in the shelter of the God who loves him. He knows his plea will be heard by his God and ultimately he will be vindicated.
The Psalm is undoubtedly set in the time when David was fleeing from King Saul. David had been marked by God as the king of his choice and yet now he is being pursued as a criminal even though he had done no wrong. The appeal therefore is for vindication. He knows he is innocent before God and that is enough for him now, but he is still anxious that God would vindicate him before his people as well. He prays therefore that He might see the favour of God at work on his behalf and that God would be faithful and just and do for David what he had promised. This psalm is a moving prayer for those who feel misrepresented in life and hemmed in by external circumstances. Innocence is given to us through Jesus Christ and this is our greatest gift. But in Jesus name we have access to the throne of God who is eager to help us overcome our circumstances and live freely the calling that he has for us.