1 John 4:1

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

2 Peter 2:1

However there were indeed false prophets among the people, as there will also be false teachers among you, whosoever shall bring in destructive heresies, even denying the Lord who bought them, bringing on themselves swift destruction.

1 John 2:18

Little children, it is the last hour: and as you have heard that antichrist is coming, even now many antichrists have come, from which we know that it is the last hour.

1 Thessalonians 5:21

but prove all things; and hold fast to the beautiful;

Luke 12:57

Why do you not judge righteous judgment, even with reference to yourselves?

Acts 17:11

but these were more noble than those in Thessalonica, who received the word with all enthusiasm, searching the scriptures daily, if these things are so.

1 Corinthians 14:29

But let two or three prophets speak, and let the others give audience;

1 Timothy 4:1

But the Spirit says positively, that in the last times certain ones will depart from the faith, giving heed to seducing spirits and to the teachings of demons,

2 John 1:7

Because many deceivers have gone out into the world, who do not confess that Jesus Christ is coming in the flesh; the same is the deceiver and the antichrist.

Revelation 2:2

I know your works, and your labor, and your patience, and that you are not able to bear the wicked; and you have tried those who say they are apostles, and are not, and have found them to be liars:

Matthew 7:15-16

But beware of false prophets, who come to you in sheep's clothing, but inwardly they are rapacious wolves.

Matthew 24:4-5

And Jesus responding said to them, See, lest any one may deceive you.

Matthew 24:23-26

Then if any one may say to you, Lo, here is Christ, or, there: believe him not:

Mark 13:21

And if then one may say to you, Lo, here is Christ; or, Lo, there; believe not.

Luke 21:8

And He said, See that you are not deceived. For many will come in my name, saying, I am He; and The time is at hand: go ye not after them.

Acts 20:29

I know, that after my departure grievous wolves will rise up against you, not sparing the flock;

Romans 16:18-19

For such do not serve our Lord Christ, but their own stomach; and through fair speeches and eulogies deceive the hearts of the innocent.

2 Timothy 3:13

But wicked men and seducers will wax worse and 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
But beware of false prophets, who come to you in sheep's clothing, but inwardly they are rapacious wolves.
Matthew 24:4
And Jesus responding said to them, See, lest any one may deceive you.
Romans 16:18
For such do not serve our Lord Christ, but their own stomach; and through fair speeches and eulogies deceive the hearts of the innocent.
2 Peter 2:1
However there were indeed false prophets among the people, as there will also be false teachers among you, whosoever shall bring in destructive heresies, even denying the Lord who bought them, bringing on themselves swift destruction.

Try

Luke 12:57
Why do you not judge righteous judgment, even with reference to yourselves?
Acts 17:11
but these were more noble than those in Thessalonica, who received the word with all enthusiasm, searching the scriptures daily, if these things are so.
Romans 16:19
For your obedience has come abroad unto all men: therefore I rejoice over you, and wish you to be wise in that which is good, and uncompromising towards that which is evil.
1 Corinthians 14:29
But let two or three prophets speak, and let the others give audience;
1 Thessalonians 5:21
but prove all things; and hold fast to the beautiful;
Revelation 2:2
I know your works, and your labor, and your patience, and that you are not able to bear the wicked; and you have tried those who say they are apostles, and are not, and have found them to be liars:

General references

Matthew 24:11
And many false prophets will arise and deceive many.
John 8:47
The one being of God hears the words of God: on account of this you do not hear, because you are not of God.
1 Corinthians 14:32
Truly the spirits of the prophets are subject to the prophets;