In hermeneutics class at MBI yesterday, one of my students proposed that Jonah received mercy via the fish appointed by God as God’s response to the prayers of the mariners:
Therefore they called out to the LORD, “O LORD, let us not perish for this man’s life, and lay not on us innocent blood, for you, O LORD, have done as it pleased you.”
By rescuing Jonah, the Lord answered the prayers of the mariners–that they would be free from the blood of Jonah. I agree with this proposal by the student.
The mariners, who have called on the Lord—who was revealed to them by the prophet, themselves receive mercy through throwing the prophet to his death in the waters. Therefore, their prayers are answered as part of their response to the gospel (in cryptic form in the OT). The Lord is answering the one prayer of unbelievers he has bound himself to answer.