True. The context of Matt. 17 is freedom for a child that was demonically oppressed and why the disciples couldn't cast out the devil. Christ clearly said "unbelief." Then he used the illustration of a mustard seed of faith, HIS FAITH TO MOVE MOUNTAINS which will always be His will. He will not oppose himself. God ALWAYS wants people free. "How God anointed Jesus of Nazareth with the Holy Ghost and with power: who went about doing good, and healing ALL that were oppressed of the devil; for God was with him." Acts 10:38