Matthew 24:4 And Jesus answered and said unto them, Take heed that no man deceive you.
Luke 21:8 And he said, Take heed that ye be not deceived: for many shall come in my name, saying, I am Christ; and the time draweth near: go ye not therefore after them.
Deception comes in many forms: cultural, literary, cinema, theater, music, songs, philosophies, sermons, prophecies, "manifestatinons of the Spirit", "angelic manifestations", signs and wonders.
The only way to avoid deception is to "take heed", keep your antennae up, and be a Berean.
Remember, just because you received a teaching or a prophecy or an email from someone you trust, does not make the message itself trustworthy.
The message must always be checked out. That is why Paul extolled the Bereans.
Acts 17:10 And the brethren immediately sent away Paul and Silas by night unto Berea: who coming thither went into the synagogue of the Jews.
11 These were more noble than those in Thessalonica, in that they received the word with all readiness of mind (that is, with an open mind), and searched the scriptures daily, whether those things were so.
Luke (and doubtless Paul, his mentor) thought the Bereans "more noble" because they didn't believe Paul without checking him out.
Nothing is lost by checking out a teaching. If it proves true, much is gained.
12 Therefore many of them believed; also of honourable women which were Greeks, and of men, not a few.
Be on guard also against "urban legends" relating to the Bible. Example: urban legends pertaining to Psalm 118
As a concrete illustration of the process, a friend received an email from a trusted friend in Malaysia, abuut potholes in the road in Mumbai. My friend sent it to me by email. In turn, I sent it to a family member, who has proved time and again that he is a Berean. he promptly checked it out and found out it was a hoax. It seemed like a joke, but we discovered it had the potential to cause accidents Here is the essential content of the email as found on the net, except that it says "Canada" where the email I received said Mumbai. The pictures are the same. According to Ads of the World, the ad was created by Advertising Agency, Y&R Everest, Mumbai, India in 2007. It is unclear under what conditions or circumstances the advertising tactic was carried out. As many commentators have noted, unless the tactic was used in very controlled conditions, such fake potholes could actually be quite dangerous. Approaching drivers could swerve suddenly to avoid the "pothole" and serious accidents could result. But the origin can be traced further back. The origin of the ad goes further back to. an ad for Ford Ranger in 2006. Ads of the World notes:
The project's purpose was to allow drivers to experience the Ford pickup's attribute of softness on hostile surfaces. In order to achieve this, several floor graphics were imprinted with cracks, snow and/or mud in various city streets. Next to them, a road signal that read "This is how it feels, Ford Ranger" was placed. Drivers drove through a difficult road without feeling it; situation that led them to experience the unique softness of riding in a Ford pickup. The floor graphics were placed in lateral streets and parking areas with speed limits that didn't exceed 10 kilometers per hour, with the objective of looking out for the driver's safety.
Such tactics might be quite effective as advertising mechanisms. However, given their potential to cause accidents, it seems doubtful that any jurisdiction would use such potholes stickers as speed limiting devices on busy roadways.
So this hoax had the potential to cause accidents and the email hoax did no one any "harm".
The same isn't true of spiritual hoaxes. They could damn the victim to an eternity in hell by leading him to believe a false gospel, or by leading him away from the true gospel of salvation.
Be a Berean! for heaven's sake!