Discernment is for the sole purpose of prayer. Yet the sole purpose of prayer is to watch and wait for answered prayer so as to act from the correct nature, otherwise it's just people pointing fingers at people.
Matt 18:15 “If your brother sins, go and show him his fault in private; if he listens to you, you have won your brother. 16 But if he does not listen to you, take one or two more with you, so that by the mouth of two or three witnesses every fact may be confirmed. 17 If he refuses to listen to them, tell it to the church; and if he refuses to listen even to the church, let him be to you as a Gentile and a tax collector. 18 Truly I say to you, whatever you bind on earth shall have been bound in heaven; and whatever you loose on earth shall have been loosed in heaven.
That bypasses the first step in the Matthew 18 process: talking to the person alone.
Jesus knew about Judas early on, no doubt, but let it play out. He tells the parable of the wheat and tares, teaching that sometimes it is more damaging to pull the weeds prematurely. Knowing something in the spirit is a protection for you, and a tool for preparing to take action at the right time. But keep praying on the timing, and for protection for everyone, and possibly for repentance of those who are in error. If you take strong action too soon, you may stumble those who can't see what you can. And there is the possibility that you are wrong as well, so waiting for something manifest can be the confirmation you need in order to justify taking action.
Receiving discernment is from God so just seek God's will in carrying out any actions as true discernment came from Him to start with. Discernment usually means judging well. In the Christian context it means "perception in the absence of judgement with a view to obtaining spiritual direction and understanding"
