Let our speech be seasoned with grace,
let us speak the truth in love, let us
build up each other in the most holy
faith, and let our words be few!!

The target for ALL christians is the perfection of God. Not that many will even come close. It is given to all those who call on the name of the Lord to turn away from all evil. Jesus spoke about the subject you site in James. But He didn't expound much. "But I tell you that men will have to give account on the day of judgment for every careless word they have spoken." Matt. 12:36

It's interesting that you should post this very thread. Just yesterday I got in trouble for calling some people to consider what they were saying in idle chit chat. And just this morning I sent a reference to that text in matthew.

How seriously terrible it will be on the day when those who stand before the Great White Throne of God realize God is not trivial. When He speaks things happen. He expects and demands that we consider our own words as carefully. What a different experience it would be in the Christian community if we took these things soberly.

By His Grace.