Then he called his twelve disciples together, and gave them power and authority over all demons, and to cure diseases.
All Commentaries on Luke 9:1 Go To Luke 9
George Leo Haydock
AD 1849
Over all devils; so that none should be able to resist them. For all were not equally easy to be expelled, as we shall see in this same chapter, in the person of a possessed child, whom the apostles could not heal, because they did not use prayer and fasting against it; and because their faith was not sufficiently strong and ardent. (Calmet)