Consider this:
'And He [Jesus] is the radiance of His glory and the exact representation of His nature, and upholds all things by the WORD OF HIS POWER.' [Hebrews 1:3]
He upholds ALL THINGS by the WORD of His power.
What is the word of His power? "POWER."
Note that it is not the power of His word, but the very word of His power.
I've heard that the exact translation of Genesis 1 in Hebrew is more like "Light, Be! Light was." instead of the more familiar "Let there be light."
In Genesis 1, the word of light was "Light."
We know that God cannot lie. [Numbers 23:19; Titus 1:2]
Why is that? Because if there was not a tree when He started to say 'tree' there would be one by the time the word was out of His mouth! He cannot lie because everything He says comes to pass!
Why Is This Important To Me?
Why? For several reasons, actually.
First, because we are one Spirit with the Lord, with the very Alpha and Omega. He is the Head, we are His body. And He said that we would do greater works than He did! [John 14:12]
Second, because He IS the WORD...
'In the beginning was the Word, and the Word was with God, and the Word was God. He was in the beginning with God. All things came into being through Him, and apart from Him nothing came into being that has come into being.' [John 1:1-3]
Third, because He told us to speak to trees and mountains. Because Psalms and Proverbs are full of instructions regarding the power of words. Because the POWER of life and death is IN THE TONGUE. [Proverbs 18:21]
Jesus knew this because He IS the Word, and He knows how the system works.
Speak His Word into the earth.
'The Lord gives the command [word]; The women who PROCLAIM the good tidings are a GREAT HOST: "Kings of armies flee, they flee, and she who remains at home will divide the spoil!" [Psalm 68:11,12]
Think of all the wonderful things He has said about and for us. His Word will come to pass...
'He sends forth His command to the earth; His word runs very swiftly.' [Psalm 147:15]
Think about it. Uphold His Word in your life by your words...