The use of the word, "ghost," is the unfortunate result of the "superstitious times" in which the King James Bible was translated.
Ghosts, spirits, goblins, etc., were fearsome things which children were taught and in which adults believed that were effective tools to help keep people on the "straight and narrow."
To the translators, ghost and spirit were interchangeable. However, they only used "Ghost" where the word "Holy" came into play.
It would have been a bit more awkward for them to try to use it where "Holy" wasn't around. For instance, it probably wouldn't have played well to read in The Bible:
"...he saw the 'GHOST' of God descending like a dove, and lighting upon Him..." (Matt.3:16).
or: "...Then was Jesus led up of the 'GHOST' into the wilderness..." (Matt.4:1).
or: "...For it is not ye that speak, but the 'GHOST' of your Father which speaketh in you." (Matt.10:20)
or: "...if I cast out devils by the 'GHOST' of God, then the Kingdom of God is come unto you." (Matt.12:28)
or: "...I will pour out of My 'GHOST' upon all flesh..." (Acts 2:17).
or: "...God hath revealed them unto us by His 'GHOST': for the 'GHOST' searcheth all things..." (I Cor.2:10).
"Ghost" never should have been used, and should have been "Spirit" in all cases. But there it is in the KJV... evidence of a superstitious people, and the effect it had on the translators' labors.
Pneuma
Pneuma is the spirit or soul - in the belief of Gnosticism, it is one of three levels of a human being - specifically the spirit, as opposed to the body or soul.
holy spirit can be translated as ru'akh hakodesh (רוח הקודש) which literally means "holy wind". Since this concept doesn't exist in Hebrew, it may be necessary to define it as well, or the person you're talking to won't understand it.
The Holy Spirit is the Lord God Almighty, the Creator of the heavens and earth. While there are several usages and meanings of the phrase "the Holy Spirit" in the scriptures, it most commonly refers to God. In the New Testament, the word "spirit" is translated from the Greek word pneuma. The Greek word hagion translates as "holy." The most basic and primary usage of the word pneuma is about God. God is pneuma, Spirit, John 4:24 Also, God is hagion, Holy, I Samuel 6:20 Thus, the Holy Spirit is God.
Yes, at one time the two words were essentially synonyms. Certain translations, most prominently the King James Authorized Edition, translate the Greek word pneuma (which literally means "breath") as "ghost" in some places. In others, it's translated "spirit" or "soul".
The phrase, "inspiration of God" (as found in 2 Timothy 3:16) literally means, "God-breathed." It is translated from the compound Greek word theopneustos (Theos = "God" + pneo = "to breathe"). Paul uses it to distinguish scripture as distinct from non-inspired writings. Inspired writings were "breathed out" by God.The role of the Holy Spirit is seen in connection with scriptural inspiration, as "spirit" is translated from the Greek word "pneuma," or "breath."
The soul or spirit in Ancient Greek is psyche (ψυχη); in later Biblical Greek pneuma (πνευμα=breath) also occurs, usually as the Spirit of God.
While the synoptic gospels speak of the Holy Spirit, using the neuter Greek word. pneuma, John's Gospel uses parakletos, literally "the One called alongside", but translated as paraclete, as a personal designation for a Spirit called in after Jesus' departure as "advocate" to defend Christians and "comforter".1 John, known to have been written in the same community as John, never uses the word paraclete or advocate for the Spirit, but does use parakletos to describe Jesus (1 John 2:1).
The word translated ghost can also be translated spirit or soul. So yes, Christians believe that God is spirit.
rooh / nafs
kokoro
The Bible provides two words in Greek that have been interpreted as spirit and soul. Pneuma, which means a breathe or a blast of air is normally interpretted as sprit. Psuche, which means to breathe or more accurately, life because of breathing, is normally interpretted as soul. The two words have been sometimes interchangeable by early scholars, but some modern scholars believe thay are different. It is their opinion that the scripture of Hebrews 4v12 shows that the soul and spirit can be divided, therefore they must be different. This belief teaches that spirit (pneuma) is the breath of life from God and that the soul (psuche) is the part of us that makes us human, that is the mind, will, and emotions. -Heb 4v12 says The Word of God is quick and powerful, and sharper than any twoedged sword, piercing even to the dividing asunder of soul and spirit, and of the joints and marrow, and a discerner of the thoughts and intents of the heart. -KJV Cool story bro