1 Cor 2:15
The person with the Spirit makes judgments about all things, but such a person is not subject to merely human judgments,..

Do you have the spirit of God and know his word?
You can use it and judge right from wrong

I Jn 4:1
Dear friends, do not believe every spirit, but test the spirits to see whether they are from God, because many false prophets have gone out into the world.


How do you test those spirits
By judging what was said using the word of God as your standard

Matt 24:11
And many false prophets shall rise, and shall deceive many.

How can you tell a true from a false prophet?
By having a sound judgement.
So should you be judging?
You bet!

Col 2:8
Don’t let anyone capture you with empty philosophies and high-sounding nonsense that come from human thinking and from the spiritual powers of this world, rather than from Christ.

How do you know those teaching you nonsense?
By your sound judgement according to the word

Phil 3:18
For, as I have often told you before and now tell you again even with tears, many live as enemies of the cross of Christ. 19Their destiny is destruction, their god is their stomach, and their glory is in their shame. Their mind is set on earthly things.

How did Paul come to this conclusion about some people who paraded themselves as believers?
By sound judgment