Jonah 2:1 - Albert Barnes' Notes on the Bible

Then - (“And”) Jonah prayed, i. e., when the three days and nights were passed, he uttered this devotion. The word “prayed” includes thanksgiving, not petition only. It is said of Hannah that she “prayed” 1 Samuel 2:1; but her canticle is all one thanksgiving without a single petition. In this thanksgiving Jonah says how his prayers had been heard, but prays no more. God had delivered him from the sea, and be thanks God, in the fish’s belly, as undisturbed as in a Church or an oratory, secure that God, who had done so much, would fulfill the rest. He called God, “his” God, who had in so many ways shown Himself to be His, by His revelations, by His inspirations, by His chastisements, and now by His mercy . “From these words, ‘Jonah prayed unto the Lord his God out of the fish’s belly,’ we perceive that, after he felt himself safe in the fish’s belly, he despaired not of God’s mercy.”