Can I Use the Ring of Truth on What He Just Said?

Archimald Celeste is a man of his word. He holds out his husky, albeit blotchy skinned hand to shake your hand. We've got a deal then. My navigating, your protection. I get to study the amulet and then I'll hand it back to you. Cyborg tells Bart to check his hand to see if the ring of truth got slipped off because this guy seems kind of sweet. Could I use the ring ofTruth on what he just said? "I was going to cast bonfire, but I'm just going to stay as a bear"