1 Corinthians 12:3

Therefore, I must tell you that no one who is speaking under the influence of the Spirit of God ever says, "Curse Jesus!" and no one can say, "Jesus is Lord!" without being under the influence of the holy Spirit.

1 John 4:1-3

Dear friends, do not believe every inspired utterance, but test the utterances to see whether they come from God, for many false prophets have come out into the world.

Revelation 16:13-14

Then I saw three foul spirits like frogs emerge from the mouth of the dragon and from the mouth of the animal and from the mouth of the false prophet.

Treasury of Scripture Knowledge

Summary

To whom hast thou uttered words? and whose spirit came from thee?

Bible References

Whose spirit

1 Corinthians 12:3
Therefore, I must tell you that no one who is speaking under the influence of the Spirit of God ever says, "Curse Jesus!" and no one can say, "Jesus is Lord!" without being under the influence of the holy Spirit.
1 John 4:1
Dear friends, do not believe every inspired utterance, but test the utterances to see whether they come from God, for many false prophets have come out into the world.
Revelation 16:13
Then I saw three foul spirits like frogs emerge from the mouth of the dragon and from the mouth of the animal and from the mouth of the false prophet.