Jesus said, "Ask and you shall receive....Whatever you ask in my name....you shall ask of the father...." All of these are only possible when we speak.
If we say nothing, we get nothing. It is really that simple.
Our mouths carry power according to Proverbs 18:21 and we will "eat the fruit of it (what we speak)", because our words are seeds.
Just like God, when we speak ...it will be...unless we stop it from 'being'.