By definition, a ghost is a spirit with his or her own personality. Every person has a spirit or soul within herself, once the body stops functioning, her spirit leaves to go somewhere, either heaven or hell. This truth is based on the teachings of Jesus Christ. You can lose your soul forever in hell if your sins are left unforgiven, after living a wanton sinful life on earth.
Jesus talked about another Person, His name is Holy Ghost or Holy Spirit. He has His own identity and personality. He is the essence of God, the Spirit of God from the beginning of time. He is called holy for He is perfect who does not need anything to live by himself.
Can we talk to the Holy Spirit? Why not? The Holy Spirit can understand heavenly tongues and languages of this world. He is an expert in mass communications. He can read our minds and actions. When we pray, the Holy Spirit can help us to articulate our longings and desires to the Almighty.
Jesus disclosed that the Holy Spirit is another Comforter to help us remember His teachings and guide us into all the truth. You see, the Holy Spitit is not an inanimate thing floating above or around us. Actually, He lives in us and empowers us to overcome the evil things of this world.
Now, we come to the scary thing about the Holy Ghost. Jesus said that blasphemy against the Holy Ghost is unpardonable sin. If you believe that Jesus was devil possessed, doing miracles under the influence of the devil rather than the anointing of the Holy Spirit, this is considered a blasphemy against the Holy Spirit which is unpardonable offense. Be afraid in offending the Holy Ghost.
Every kingdom divided against itself is brought to desolation; and every city or house divided against itself shall not stand: 26 And if Satan cast out Satan, he is divided against himself; how shall then his kingdom stand? 27 And if I by Beelzebub cast out devils, by whom do your children cast them out? therefore they shall be your judges.
28 But if I cast out devils by the Spirit of God, then the kingdom of God is come unto you. 29 Or else how can one enter into a strong man’s house, and spoil his goods, except he first bind the strong man? and then he will spoil his house. 30 He that is not with me is against me; and he that gathereth not with me scattereth abroad.
31 Wherefore I say unto you, All manner of sin and blasphemy shall be forgiven unto men: but the blasphemy against the Holy Ghost shall not be forgiven unto men.
32 And whosoever speaketh a word against the Son of man, it shall be forgiven him: but whosoever speaketh against the Holy Ghost, it shall not be forgiven him, neither in this world, neither in the world to come. Matthew 12:25-32