And he hath put a new song in my mouth, even praise unto our God: many shall see it, and fear, and shall trust in the LORD. A new song - Cheerfulness and joy had long been strangers to him. He seemed to live to utter the most doleful complaints, and be a prey to suffering and wretchedness. Praise for a sense of God's favor was a new song to him. The word is often used to signify excellence: I will sing a most excellent and eminent song.
Many shalt see it - I will publish it abroad and fear-to sin against the Lord, knowing by my example what a grievous and bitter thing it is.
And shall trust in the Lord - Even the worst of sinners shall not despair of mercy, being penitent, when they see that I have found favor in his sight.