But I trusted in Your mercy. My heart will rejoice in Your salvation.
With the words “But I,” the direction of the psalm changes. Nothing is yet said about a change in the outward situation, but David’s heart finds a new foundation: God’s mercy. He does not rely on his own strength, merit, or the steadiness of his feelings. The Lord’s faithful love is the basis of his confidence. The word “I have trusted” recalls a choice made in the past and continuing in the present. David decides to place his burden on God’s mercy. The result of this is the joy he expects. He still asks for salvation, yet already rejoices in it by faith. The believer’s joy sometimes begins before circumstances change, because it is grounded in God’s character. In this verse there is no artificial joy. It shows that even in deep sorrow it is possible to hold fast to the promise of the Lord’s mercy and receive new hope from it.