The Scriptures state that in order to effectively deal with powerful spiritual entities, one must first bind them. When you are trying to cast demonic spirits out of someone, or are seeking to heal them, first ask the Holy Spirit that is in you to bind every demon or evil spirit that is in the person and cast it out of them into the abyss.
Speak in the language of the spirit, from the heart, powerfully and with deep conviction. The Lord God Almighty seeks to have everyone in the kingdom of God become a healer. The Lord God Almighty desires to have a kingdom that is completely healed of every illness and disease.
The Lord God Almighty El Shaddai