1 John 4:1

Beloved, do not believe every spirit, but test the spirits to see whether they are of God; because many false prophets have gone out into the world.

2 Peter 2:1

But false prophets also arose among the people, just as there will also be false teachers among you, who will secretly introduce destructive heresies, even denying the Master who bought them, bringing swift destruction upon themselves.

1 John 2:18

Little children, it is the last hour; and as you have heard that the Antichrist is coming, even now many antichrists have come; by this we know that it is the last hour.

1 Thessalonians 5:21

But test everything; hold fast to what is good.

Luke 12:57

"And why do you not judge for yourselves what is right?

Acts 17:11

Now these were more noble-minded than those in Thessalonica, for they received the word with great eagerness, examining the Scriptures daily to see if these things were so.

1 Corinthians 12:10

and to another the working of miracles, and to another prophecy, and to another distinguishing between spirits, to another various kinds of tongues, and to another the interpretation of tongues.

1 Corinthians 14:29

Let two or three prophets speak, and let the others weigh what is said.

1 Timothy 4:1

Now the Spirit expressly says that in later times some will fall away from the faith by giving heed to deceitful spirits and doctrines of demons,

2 John 1:7

For many deceivers, who do not acknowledge Jesus Christ as coming in the flesh, have gone out into the world. Any such person is the deceiver and the antichrist.

Revelation 2:2

I know your works, your toil and your patient endurance. I know that you cannot bear evil men, but you have tested those who call themselves apostles and are not, and have found them to be false;

Revelation 2:2-5

I know your works, your toil and your patient endurance. I know that you cannot bear evil men, but you have tested those who call themselves apostles and are not, and have found them to be false;

Revelation 2:2

I know your works, your toil and your patient endurance. I know that you cannot bear evil men, but you have tested those who call themselves apostles and are not, and have found them to be false;

Revelation 2:2

I know your works, your toil and your patient endurance. I know that you cannot bear evil men, but you have tested those who call themselves apostles and are not, and have found them to be false;

Revelation 2:2-9

I know your works, your toil and your patient endurance. I know that you cannot bear evil men, but you have tested those who call themselves apostles and are not, and have found them to be false;

Matthew 7:15-16

"Beware of false prophets, who come to you in sheep's clothing, but inwardly they are ravenous wolves.

Matthew 24:4-5

And Jesus answered them: "Take heed that no one deceives you.

Matthew 24:23-26

Then if any one says to you, 'Look, here is the Christ!' or 'There he is!' do not believe it.

Mark 13:21

Then if anyone says to you, 'Look, here is the Christ!' or, 'Look, he is there!' do not believe it.

Luke 21:8

And he said: "Take heed that you not are deceived. For many will come in my name, saying, 'I am he,' and, 'The time is near.' Do not go after them.

Acts 20:29

I know that after my departure savage wolves will come in among you, not sparing the flock;

Romans 16:18-19

For such persons do not serve our Lord Christ, but their own appetites, and by smooth and flattering words they deceive the hearts of the simple.

2 Timothy 3:13

while evil men and impostors will go from bad to worse, deceiving and being deceived.

Treasury of Scripture Knowledge

Summary

Beloved, believe not every spirit, but try the spirits whether they are of God: because many false prophets are gone out into the world.

Bible References

Believe not

Matthew 7:15
"Beware of false prophets, who come to you in sheep's clothing, but inwardly they are ravenous wolves.
Matthew 24:4
And Jesus answered them: "Take heed that no one deceives you.
Romans 16:18
For such persons do not serve our Lord Christ, but their own appetites, and by smooth and flattering words they deceive the hearts of the simple.
2 Peter 2:1
But false prophets also arose among the people, just as there will also be false teachers among you, who will secretly introduce destructive heresies, even denying the Master who bought them, bringing swift destruction upon themselves.

Try

Luke 12:57
"And why do you not judge for yourselves what is right?
Acts 17:11
Now these were more noble-minded than those in Thessalonica, for they received the word with great eagerness, examining the Scriptures daily to see if these things were so.
Romans 16:19
For your obedience has become known to all, so I am full of joy over you; but I want you to be wise about what is good, and innocent about what is evil.
1 Corinthians 14:29
Let two or three prophets speak, and let the others weigh what is said.
1 Thessalonians 5:21
But test everything; hold fast to what is good.
Revelation 2:2
I know your works, your toil and your patient endurance. I know that you cannot bear evil men, but you have tested those who call themselves apostles and are not, and have found them to be false;

General references

Matthew 24:11
And many false prophets will rise up and deceive many.
John 8:47
He who is of God hears the words of God; the reason you do not hear them is that you are not of God."
1 Corinthians 14:32
and the spirits of prophets are subject to prophets.