There are certain mountains that by merely speaking once, they will vamoose, but there will be some that you need to keep speaking to consistently before they disintegrate. So, no matter how long it takes, God expects us never to doubt that the mountain will be out of our way.
The scripture commands that We say to the mountain and not to God. That is because God is making it clear to you and I today that the miracle is in our mouth and He has made us to be that powerful over our circumstances and what our lives amount to.
The mountain from our scripture is a non-living thing. Invariably, Jesus is trying to make us understand that irrespective of what the challenge is ALL we have to do is speak to or into it – Dear ones, it is a blank cheque for you to fill in anything you desire on it. Wow! God is awesome.