Elijah used this prayer when he stopped the rain from heaven and started it again after three and one half years.
The Lord Jesus teaches us to speak to the mountain. Look at these passages:
Matthew 17:20 So Jesus said to them, “Because of your unbelief; for assuredly, I say to you, if you have faith as a mustard seed, you will say to this mountain, ‘Move from here to there,’ and it will move; and nothing will be impossible for you.
Matthew 21:21 So Jesus answered and said to them, “Assuredly, I say to you, if you have faith and do not doubt, you will not only do what was done to the fig tree, but also if you say to this mountain, ‘Be removed and be cast into the sea,’ it will be done.
Mark 11:23 “For assuredly, I say to you, whoever says to this mountain, ‘Be removed and be cast into the sea,’ and does not doubt in his heart, but believes that those things he says will be done, he will have whatever he says.
So when the Lord gives us a mountain He wants us to speak to it. Let me say it another way. When we encounter some difficult thing in life, the Lord wants us to speak to the thing. How do you pray or speak then it seems impossible and one can only see in faith that God can do something.