Why would anyone ever want to take a prayer back?
No one who offers one in sincerity would even consider such a thing. And anyone who didn’t offer it in sincerity, well it never mattered what they did anyway. It’s not who deserves it or who we believe deserves it—(because we humans are so good at determining those things) it’s that all of us need it. Possessing compassion doesn’t need to be so difficult.