One of the core beliefs of Orthodox Judaism is that God appeared at Mount Sinai and said in a thundering voice, "Yeah, it's all true." From a Bayesian perspective that's some darned unambiguous evidence of a superhumanly powerful entity. (Albeit it doesn't prove that the entity is God per se, or that the entity is benevolent - it could be alien teenagers.)

I think this phrasing, particularly of the parenthetical portion, is a low-level but still present existential risk, because the temptation it creates for teenagers such as myself to actually say in the future "This is your god speaking" to an alien world is enormous. The potential negative consequences this could have on said alien world is astronomically enormous.