But I with the voice of thanksgiving will sacrifice to you; what I have vowed I will pay. Salvation belongs to the LORD!”
Jonah says this from inside the belly of a fish, having spent three days there after running as hard as he could from the exact assignment God gave him. This isn't a prayer from someone who's been faithful all along and is simply thanking God for expected help. It's a prayer from someone who fled, got swallowed, and is only now admitting where real rescue actually comes from.
That context changes the weight of the last line. "Salvation belongs to the LORD" isn't a slogan here — it's a correction Jonah is making about his own life, out loud, from the one place he can't run anywhere else. He'd tried outrunning the assignment. It didn't work. The only way out was admitting he wasn't the one who was going to save himself.
If you've been running from something you suspect God is asking of you, or just running from the whole question generally, this verse comes from someone who knows exactly what that feels like, right up until it stops working.
If you've been running from a question you suspect matters, Jonah's prayer from the deep is worth reading before you're forced to.
A short video on this is coming soon — for now, read on.