The Christian life requires us to speak words that contain both grace and truth. If you go to one extreme and only say encouraging things without combining it with truth, then it is really not grace anymore.
One the other hand if you only speak truth without any awareness of saying the right thing, the right way, at the right time, then people will never receive what they need to hear. This post by Ann Voskamp is incredible and well worth the read:
“It’s a loud, deafening war of words out there and when I stand in the farm woods these days, looking up into the outstretched arms of trees, I have to wonder:
When a leaf falls in the woods, and there is actually someone to hear it, why does it sound so much like the quietness of grace?
It’s like all the trees of the woods are asking the people in the streets: How can you all sound alot more like grace?
Because: The way words are spoken matters to the One who is the Word, who is the Way.
What we say and how we say it matters, because we are the people who believe that is was the Word that created matter. Words create actual matter — for good or for evil –in the world.”