Notice the latter part of the verse: He does whatever you require for Him to do for you, by His power that's at work in you, not by the power He wields in, or from heaven. That's why when those types of miracles happen, He gives you credit. He told us to heal the sick, cleanse the lepers, raise the dead, and cast out demons (Matthew 10:8). He didn't tell us to pray to do those things!