Many bookstores have books on ghosts, demons and alike. It is a witness to the general public's acceptance of the spirit world.
The word of God contains eyewitness accounts of Jesus' encounters with God's chief adversary - the devil, as well as the angels he deceived (demons). Christ came to earth and assumed the form of a human to pay the price for sin for all man. In order for him to accomplish this goal Christ had to first overcome and triumph over the devil. Satan's very real presence is testified in the scriptures.
1 Therefore, being engaged in this service and being mindful of the mercy which has been shown us, we are not cowards. 2 Nay, we have renounced the secrecy which marks a feeling of shame. We practice no cunning tricks, nor do we adulterate God’s Message. But by a full clear statement of the truth we strive to commend ourselves in the presence of God to every human conscience. 3 If, however, the meaning of our Good News has been veiled, the veil has been on the hearts of those who are on the way to perdition . . . (2 Corinthians 4)
1 To you Gentiles also, who were dead through your offences and sins, 2 which were once habitual to you while you walked in the ways of this world and obeyed the Prince of the powers of the air, the spirits that are now at work in the hearts of the sons of disobedience - to you God has given Life. (Ephesians 2:1-2)
After going without food to almost dying, and had prayed many hours, He allowed the devil to take him physically place to place. God's word states Christ was brought to the very top of one of Jerusalem's buildings.
During Jesus' ministry he ran into those 'bothered' by the demon world. When his ministry finally ended there were many who were still bothered by demons, or possessed by them, as there were still a whole lot of people who were still sick.
While performing His ministry people came and asked Christ for mercy because of someone they loved dearly who was trouble by a demon. The book of Matthew says there was a time when someone came and begged him for something special.
14 When they had returned to the people, there came to Him a man who fell on his knees before Him and besought Him. 15 'Sir,' he said, 'have pity on my son, for he is an epileptic and is very ill. Often he falls into the fire and often into the water. 16 I have brought him to your disciples, and they have not been able to cure him.' . . . 18 Then Jesus reprimanded the demon, and it came out and left him; and the boy was cured from that moment. 21 But an evil spirit of this kind is only driven out by prayer and fasting.' Matthew 17:14-21
Though many no doubt thought he was likely dead, Christ took the young lad by his hand and caused him to get up on his feet. The boy looked around and wondered just what happened to him!
Jesus gave them a gentle rebuke by saying some evil spirits were harder to deal with than others.
There was a time when Christ was near the cities of Sidon and Tyre when a woman was bothering the disciples for something she wanted (see Matthew 15:21-28).
The woman was able, among the crowd, to distinguish who Jesus was and began to cry loudly.
The woman said she knew he was Jesus and that he could help her with her daughter. Jesus did not respond to the woman. Insisting for an answer, Jesus finally said he was to go to only the house of Israel - Israelites. This no doubt reinforced the attitude among the disciples that the woman was a pest. But persist she did.
She ultimately had to kneel before Jesus and beg for help. Christ still refused her. He then gave the unusual analogy of taking food from the dinner table and offering it to dogs. Her answer of humility was ultimately able to win her the healing she desired.
Born of Spirit
Jesus was aware always of another dimension - one that is spiritual.
33 'You sent to John, and he both was and still is a witness to the truth. 34 But the testimony on my behalf which I accept is not from man; though I say all this in order that you may be saved. 35 He was the lamp that burned and shone, and for a time you were willing to be gladdened by his light. 37 And the Father who sent me, He has given testimony concerning me. None of you have ever either heard His voice or seen what He is like. (John 5)
This awareness gave Jesus the ability to understand human nature. He could instantly read a person's mind and know where they are coming from.
Jesus told those who exchanged money to get out of the temple - God's house of prayer - and not make it into a place of thieves. Then some self-righteous Jewish leaders sternly demanded a sign. Jesus refused.
18 So the Jews asked Him, 'What proof of your authority do you exhibit to us, seeing that you do these things?' 19 'Demolish this Sanctuary,' said Jesus, 'and in three days I will rebuild it.'
John said that Jesus spoke about the temple - meaning his physical body. John also said that it was only after his resurrection that the disciples remembered what he said regarding him being raised from the dead.
Christ did not fully trust man, which means he did not reveal exactly who he was or what all the details of his mission. He did not want to put himself in a compromised position and knew how human nature could behave.
One day a religious leader named Nicodemus came to see Jesus. After he admitted that Jesus truly did come from God he stated that no one could do the miracles that he did unless God was with them. Jesus responded by saying,
1 Now there was one of the Pharisees whose name was Nicodemus—a ruler among the Jews. 2 He came to Jesus by night and said, 'Rabbi, we know that you are a teacher from God; for no one can do these miracles which you are doing, unless God is with him. 3 'In most solemn truth I tell you,' answered Jesus, 'that unless a man is born anew he cannot see the Kingdom of God.' 4 'How is it possible,' Nicodemus asked, 'for a man to be born when he is old? Can he a second time enter his mother’s womb and be born?' 5 'In most solemn truth I tell you,' replied Jesus, 'that unless a man is born of water and the Spirit, he cannot enter the Kingdom of God. 6 Whatever has been born of the flesh is flesh, and whatever has been born of the Spirit is spirit. (John 3)
Nicodemus asked whether a man can be born when he is old. Having seen him personally on some occasions, and having heard all the rumors, Nicodemus seemingly wanted to be convinced further.
He told Nicodemus, "that unless a man is born of water and the Spirit, he cannot enter the Kingdom of God."
What Jesus said absolutely puzzled Nicodemus - that someone "born of the spirit" was literally spirit! Nicodemus wonder aloud how could these things be. Jesus then told Nicodemus He was thinking "earthly" then asked him another question.
10 'Are you,' replied Jesus, '‘the Teacher of Israel,’ and yet do you not understand these things? 11 In most solemn truth I tell you that we speak what we know, and give testimony of that of which we were eye-witnesses, and yet you all reject our testimony. 12 If I have told you earthly things and none of you believe me, how will you believe me if I tell you of things in Heaven?
Jesus was trying to tell Nicodemus parts of the gospel message - trust in him as Savior; believe that he will be resurrected and accept it, etc. and the plain fact that only those born of spirit are born again.