Whoever believes and is baptized will be saved, but whoever does not believe will be condemned.

And these signs will accompany those who believe:

• in my [Jesus] name [authority] they will cast out demons;
• they will speak in new tongues;
• they will pick up serpents with their hands; and
• if they drink any deadly poison, it will not hurt them;
• they will lay their hands fon the sick, and they will recover.”

-- Mark 16:16-18

Note that these are no requirements for salvation, but only signs to help identify who are saved and could potentially be trusted. These instructions were given by Jesus in a world where:

• his disciples were persecuted and trusting the wrong people could be a deadly mistake
• no bibles were published yet, so there were no intellectual way to verify any preaching
• there were many false prophets around
• there were many false teachers

But false prophets also arose among the people, just as there will be false teachers among you, who will secretly bring in destructive heresies, even denying the Master who bought them, bringing upon themselves swift destruction. And many will follow their sensuality, and because of them the way of truth will be blasphemed. And in their greed they will exploit you with false words. -- 2 Peter 2:1-3 (ESV)

In the book of Galatians Paul address a false teaching that confused his followers. I cannot quote the entire book here, but I would encourage you to read it. However, I will highlight a few scriptures from it:

Now the works of the flesh are evident:

• sexual immorality,
• impurity,
• sensuality,
• idolatry,
• sorcery,
• enmity,
• strife,
• jealousy,
• fits of anger,
• rivalries,
• dissensions,
• divisions,
• envy,
• drunkenness,
• orgies, and things like these.

I warn you, as I warned you before, that those who do such things will not inherit the kingdom of God.

But the fruit of the Spirit is

• love,
• joy,
• peace,
• patience,
• kindness,
• goodness,
• faithfulness,
• gentleness,
• self-control;

against such things there is no law. And those who belong to Christ Jesus have crucified the flesh with its passions and desires.

-- Galatians 5:19-24

Again, this is not a list of prerequisites for salvation, but indicates which spirit is at work and whether a message should be trusted or rejected. This includes church meetings, sermons, videos, books, websites, but especially prophecies which usually cannot be confirmed or denied by bible scripture alone.