In the Kingdom of Heaven, on earth, our words are powerful. The power of death or life is in our tongue; they that love it[either one] shall eat the fruit thereof. Christ in Matt. 8:5-10 was sought and found by a Centurion who had a sick servant; He requested that Christ "speak the word only" to heal his servant.
The Scripture states that Christ "marveled" and said that He had not seen this kind of faith in Israel. What kind of faith? Christ at a weak point, spoke "get the hence Satan." A fig* tree was in Christ way, and He spoke, causing the fig tree to wither and die. I can do all through Christ...
Without faith, it is impossible to please God. We must speak the Word and believe. Call those things[person, place, or things] that be not as though they were. Speak to the mountains[Matt.21:19-21] in our lives.
The entire New Testament is on Kingdom business, on earth. All of the "Be-attitudes" is Kingdom teachings. Idol words are forbidden; these are just the opposite of the Centurion who knew that He was a man under authority, yet having soldiers under himself. "I say to this man go, and he goes." This is how our Angels work with, and for us.
This Centurion got it. He understood authority. It works the same way in a kingdom, and especially so in the Lord's Kingdom on earth. "Repent", for the Kingdom of Heaven is here. The Gospel of the Kingdom of Heaven is what is to be spread across the earth; anything else is the Traditions of Men.