As a follower of Christ our tongues are not our own; Jesus is to be Lord of our speech.
There are those that feel they cannot speak the truth as there would be terrible consequences. We should seek to live in a way that shows what we believe to be true. Integrity is the only way to have a whole and healthy life where inner conviction matches with external action.
Living a double life may save your body but it can damage your soul. God gave us a tongue that we may honour him and speak the truth as He does.
Truth is at the heart of every strong relationship but if we lie to others we can start to deceive ourselves as well. Conflict in community can be caused by not keeping one's word.
Misunderstandings, mistakes and external circumstance beyond our control can cause us to not keep our word. If someone doesn't keep their word, exercise grace and forgiveness but stand for the truth. We can't do this on our own strength, so look to God.