Jesus said to them, “That kind of spirit does not come out in any other way except by fasting and prayer.”
The Lord reveals that certain spiritual battles require a deeper dependence on God. Prayer is the lifting up of a person’s soul toward God, and fasting is the humbling of one’s fleshly self-confidence. Together these show that victory does not come mechanically or by the power of graces received once for all, but through living communion with God. The disciples may have learned to minister with the authority they had received, but in this case they lacked the inner readiness that comes through a life of prayer and self-denial. This word is an important reminder for the church of all times: the real struggle against evil is not overcome by outward form, but by holiness, prayer, and complete reliance on God.