1 Thess 5:21 tells us,
"Prove all things, hold fast to that which is good."
In other words, don't believe everything you here. Make people PROVE to you an idea is true before accepting it.
A lot of damage can be done to the Gospel if we don't "Prove all things" first. If we accept a crazy idea, and then pass it on as truth, and people think it is crazy, then they are not going to listen to you when you try to tell them about the Gospel.
This is one of the reasons why I feel like I am helping to defend the credibility of the Gospel by dispelling what are sometimes wild ideas that occasionally float around the body of believers. I think Satan sometimes spreads rumors just to see if we will swallow them and pass them on in order to damage our credibility. There is a lot of misinformation out there. And if you don't do what the Scriptures say about "Prove all things." then there may not be as many people joining us in the world to come.
Don't pass on everything you hear as true. You may end up causing people to think you're gullible, and if you project that image, they may end up only thinking that faith in what you can't see is for people who are gullible. There are a lot of people out there who HAVE come to that conclusion - don't enhance that view by making them think you're another person confirming their opinion.
Some strange ideas are true. But wait until you can "PROVE" them, as 1 Thess 5:21 says, before you pass them on. Some conspiracy theories are true. But wait until the evidence rolls in before you tell other people you believe one. They can't all be true. In fact one of the easiest ways to bury a true conspiracy is to spread lies that there are 200 false ones. It will create the "cry wolf" effect to cause people not to believe any of them.
One reason some people swallow bad ideas is that they don't realize they have more options than either to believe or reject an idea. If you're not sure if an idea is true, remain neutral until enough evidence comes in. You don't have to decide yes or no right away.
Shalom,
Joe