Ralph M. Riggs explained the different forms of demons, which we encounter in the Bible, and how to excorcise them (this means: how to cast them out):
‘In the realm of affliction, the Bible speaks of dumb spirits, Matt. 9:32; Mark 9:17; blind spirits, Matt. 12:22; deaf spirits, Mark 9:25; spirits of infirmity, Luke 13:11, 16; and spirits of lunacy, Matt. 17:15, 18. There are also cases of those who were just “possessed with devils (demons).” Matt. 4:24; 8:16, 28; Acts 8:7; 16:16. The gift of discerning spirits will enable the worker to approach these cases with knowledge and understanding. With the word of authority, he casts out the evil spirit. Mark 16:17.’
– Ralph M. Riggs, The Spirit Himself (1949), Introduction, Pentecostal People are Orthodox, p. xii-xiii.
In conclusion: We, Christians, have no need to be afraid of demons or of the devil, since we are the children of God and He (that is, according to how I interpret this verse: the Holy Spirit) who is in us, is greater than he (that is: the devil) who is in the world. We can and should cast out demons by using the Name of Jesus.
Thomas A Kempis has certainly learned how to deal with the devil:
“Do not believe him [the devil] or heed him, even though he often sets traps to deceive you. When he suggests evil, unclean things, accuse him. Say to him: “Away, unclean spirit! Shame, miserable creature! You are but filth to bring such things to my ears. Begone, most wretched seducer! You shall have no part in me, for Jesus will be my strength, and you shall be confounded. I would rather die and suffer all torments than consent to you.”
– Thomas A Kempis, The Imitation of Christ, Book III: Internal Consolation, Chapter VI: The Proving of A True Lover. [Source: Christian Classics Ethereal Library]