The Bible has much to say about deception by false prophets, signs and wonders. Our safeguard against being led astray is to have our faith anchored in the living Word of God.
A Warning About False Prophets
Throughout history God has communicated his will to his servants the prophets. The prophets heard from God and then spoke to the people. But there were also false prophets. And we are left in no doubt how to identify one who is a false prophet.
"If a prophet, or one who foretells by dreams, appears among you and announces to you a miraculous sign or wonder, and if the sign or wonder of which he has spoken takes place, and he says, 'Let us follow other gods' (gods you have not known) 'and let us worship them,' you must not listen to the words of that prophet or dreamer… because he preached rebellion against the LORD your God'." (Deuteronomy 13:1-3) A reasonable question would present itself at this stage. "You may say to yourselves, 'How can we know when a message has not been spoken by the LORD?' 'If what a prophet proclaims in the name of the LORD does not take place or come true, that is a message the LORD has not spoken. That prophet has spoken presumptuously. Do not be afraid of him." (Deuteronomy 18:21-22)
False prophets were infiltrating the church and the Apostle John was compelled to give this warning: "Dear friends, do not believe every spirit, but test the spirits to see whether they are from God, because many false prophets have gone out into the world." (1 John 4:1) And our Lord also warned about being deceived by falsehood: "For false Christs and false prophets will appear and perform great signs and miracles to deceive even the elect - if that were possible." (Matthew 24:24)
These scriptures make the following points: A false prophet can foretell future events, perform signs and wonders, which may defy explanation, and at the same time proclaim a message that is a contradiction of the truth. Such a prophet is not from God irrespective of his 'credentials.'
Examining the Message
People are gullible. They are willing to believe almost anything. News of 'a sign or wonder' or 'a prophetic word' will receive much attention while very little or no thought is necessarily given to the message itself.
There are those who claim to be speaking for God with a message from God. Are we to believe everyone who makes such a claim? The world of religious cults and some extreme religious movements claim they are speaking for God, yet they all have conflicting messages. How could all this be from God?
Any 'prophetic word' must be measured against the truth revealed in scripture. Otherwise, we leave ourselves wide open to being deceived.