1 Corinthians 14:29

And [only] two or three prophets should speak [in one meeting], and [then] other people should determine the significance [of their messages].

1 Corinthians 12:10

Another [is given] the ability to perform miracles; and another [is given] the ability to prophesy [supernaturally]; and another [is given] the ability to speak in different languages [supernaturally]; and still another [is given] the ability to interpret those languages [supernaturally].

1 Corinthians 14:39

Therefore, my brothers, desire eagerly to prophesy and [yet] do not prohibit people from speaking in a language [supernaturally].

1 Thessalonians 5:19-21

Do not squelch the [influence of the] Holy Spirit [in your lives].

1 John 4:1-3

Loved ones, do not believe [the message of] every spirit [i.e., every person claiming to be a teacher], but test the spirits [i.e., require proof that they and their message are genuine] to see whether they represent God [or not], because many false prophets have begun circulating throughout the world.

Treasury of Scripture Knowledge

Summary

Let the prophets speak two or three, and let the other judge.

Bible References

The prophets

1 Corinthians 14:39
Therefore, my brothers, desire eagerly to prophesy and [yet] do not prohibit people from speaking in a language [supernaturally].
1 Corinthians 12:10
Another [is given] the ability to perform miracles; and another [is given] the ability to prophesy [supernaturally]; and another [is given] the ability to speak in different languages [supernaturally]; and still another [is given] the ability to interpret those languages [supernaturally].
1 Thessalonians 5:19
Do not squelch the [influence of the] Holy Spirit [in your lives].
1 John 4:1
Loved ones, do not believe [the message of] every spirit [i.e., every person claiming to be a teacher], but test the spirits [i.e., require proof that they and their message are genuine] to see whether they represent God [or not], because many false prophets have begun circulating throughout the world.

General references

1 Corinthians 14:32
And the prophets' spirits are [to be] under the prophets' control [i.e., a prophet was to determine if or when he exercised his gift],
1 Thessalonians 5:20
Do not look down on prophetic messages.