Jesus spent a considerable amount of His time on earth dealing with demons (aka evil spirits, unclean spirits, etc). This was one of His main activities. It was also one of the things that really drew people to him. Take a look at these passages.
When evening had come, they brought to Him many who were demon-possessed. And He cast out the spirits with a word, and healed all who were sick,
Then He healed many who were sick with various diseases, and cast out many demons; and He did not allow the demons to speak, because they knew Him
39 And he went throughout all Galilee, preaching in their synagogues and casting out demons.
And the unclean spirits, whenever they saw Him, fell down before Him and cried out, saying, “You are the Son of God.”
Then they were all amazed and spoke among themselves, saying, “What a word this is! For with authority and power He commands the unclean spirits, and they come out.”
And He came down with them and stood on a level place with a crowd of His disciples and a great multitude of people from all Judea and Jerusalem, and from the seacoast of Tyre and Sidon, who came to hear Him and be healed of their diseases,as well as those who were tormented with unclean spirits. And they were healed.
And that very hour He cured many of infirmities, afflictions, and evil spirits; and to many blind He gave sight.
Preaching, teaching, healing the sick, and casting out demons. That’s what you would see if you went to see Jesus in action. He would preach the Kingdom of God, and then demonstrate it with displays of supernatural power. Or, He would do it in reverse order. He would exercise supernatural power over sickness and demons, and then He would preach and teach.
That is what the ministry of Jesus looked like. Casting out demons was a big part of it. It was one his three main areas of focus (with healing and preaching/teaching being the other two).
Also, we know from scripture that it was important to him that his representatives do this also as a regular part of their activities.
We can see it when he sent out the 12 (his first group of representatives):
Luke 9:1 – Then He called His twelve disciples together and gave them power and authority over all demons, and to cure diseases. He sent them to preach the kingdom of God and to heal the sick.
We can also see it when he sent out the 70 (his second group of representatives):
Luke 10:1 – After these things the Lord appointed seventy others also, and sent them two by two before His face into every city and place where He Himself was about to go….
Luke 10:17-19 – Then the seventy returned with joy, saying, “Lord, even the demons are subject to us in Your name.” And He said to them, “I saw Satan fall like lightning from heaven. Behold, I give you the authority to trample on serpents and scorpions, and over all the power of the enemy, and nothing shall by any means hurt you…”
Also, at the great commission, this is the first thing Jesus mentioned when he was describing the signs that “shall follow them that believe”:
Mark 16:17 – And these signs will follow those who believe: In My name they will cast out demons; they will speak with new tongues…
When Jesus prepared people and sent them out to represent Him, casting out demons was part of the program. This is because He loves people, and wants them to be free from the influence of evil spirits, just like He wants people to be saved and healed.
As the Bible narrative continues in the book of Acts, you can see His followers dealing with demons as part of what they did. This wasn’t just something that happened during the ministry of Jesus before He died on the cross. It continued, just like healing and preaching/teaching continued. Those are the three main activities that followers of Jesus are supposed to be equipped for. That our mission as Christians. We are supposed to doing the works that Jesus did (John 14:12) which means healing the sick, casting out demons, and preaching the gospel.
When teaching people about the different parts of the Christian walk, we should include training on dealing with demons. It should be a major area of focus, since it will be a regular part of our activities. There aren’t any less demons in the world now than there were 2000 years ago. And a representative of Jesus should be able (at least to some degree) to recognize demonic activity, to exercise authority over demons, and to drive them out of anyone that is being oppressed. This is a balanced, proper, and Biblical perspective.