I went to a wedding today. As the couple made their vows before God, it reminded me of how important our words are. For the law of the land, there has to be a legal document signed, but before God it is our words that are binding. It is once they have made their confession before God and man that they are declared husband and wife, not after they have signed the register.
These days people put little value on words. These are cynical times, and there have been too many promises broken. Unless you "have it in writing" it seems that a person's word means very little. (Anyone who has moved house in England will know what I mean!)
But it was not so in Biblical times, and it is not so before God. When Joshua made a promise to the Gibeonites not to destroy them, and then found out that this was in conflict with a direct command from God, he did not say - "Phew, good job they don't have anything in writing." He had given them his word, and his word was binding.
It is not just in making promises that our words are binding either. Jesus said: "Whatever you bind on earth will be bound in heaven". How do we do this if not through our declaration?
God has invested a lot of power and authority in our words, it's no wonder the Bible has so much to say about how we use them. We should not use our words lightly, or use them against a brother or sister in Christ. We should use them wisely for the advance of his Kingdom.