Rock on, Pat!
If he feels people are at risk, he should tell them. If he keeps it a secret, he's a jerk. If he feels God will punish people as so OFTEN is shown in the Bible, it is nice to tell them so.
Let's pretend they were on a bridge and he knows that on the other side, the bridge is out. He flags people and says WARNING, STOP fast. They might get mad and tell him he's nuts. They like driving on that road. They feel good on that road. Their friends all tell them that road is the right one... see what I'm saying? Now, assume he sat back and did nothing. He sat there and watched car after car, thinking they were safe, plunge into the water below. Now, THAT would be a mean son of a gun.
If he blelieves it, he sould say so. People don't have to listen. Since we are in America, we have other options on TV. We have a free country where not all broadcasting is by a corrupt government who kills people for having a different faith then those in power.
I say, hope he's wrong.
But what if he's right? We know at least he THINKS he's right and in that case, he's doing the right thing.
Let's assume he's a prophet, for a minute. How many prophets were LIKED in the Bible? People hate the message and so they hate the men. It didn't change, even once, that the message was true.
Now, I am not saying his message IS right. I hope it's not.