Ghosts are not the spirits of the deceased
The Bible teaches that the dead are sleeping in their graves awaiting the resurrection. “All that are in the graves shall hear his voice, And shall come forth” (John 5:28, 29). The prophet David is dead yet he has not ascended to heaven. “David … is both dead and buried, and his sepulchre is with us unto this day.” “For David is not ascended into the heavens” (Acts 2:29, 34).
What happens at death?
After death a person: returns to dust (Psalms 104:29), knows nothing (Ecclesiastes 9:5), possesses no mental powers (Psalms 146:4). He has nothing to do with anything on earth (Ecclesiastes 9:6), does not live (2 Kings 20:1). He waits in the grave (Job 17:13), and continues not (Job 14:1, 2) until the resurrection (Revelation 22:12; 1 Thessalonians 4:16, 17; 1 Corinthians 15:51-53).
Since the dead know nothing, it is obvious that they cannot appear to people or be consulted. So, if these appearances or apparitions are not our beloved deceased ones, then who are they? God’s Word explains that all supernatural activity-aside from God and His angels – is from the devil (1 Corinthians 10:20; Deuteronomy 32:17).
Why is this so important to know today?
The Bible predicts that at the end of time, people will become more open to the teachings of deceiving spirits (1 Timothy 4:1). Satan will use sorcery (the supernatural agency that claims to receive its power and wisdom from the spirits of the dead) to deceive the world (Revelation 18:23).
Through miracles and supernatural acts (Revelation 16:14; Matthew 24:24), the devil and his demons will pose as deceased godly loved ones, Bible prophets, apostles of Christ (2 Corinthians 11:13), or even as Christ Himself (Matthew 24:23, 24) to deceive the world.
The Bible warns that we should reject the spirits that claim to be the spirits of the dead “And when they say to you, “Seek those who are mediums and wizards, who whisper and mutter,” should not a people seek their God? Should they seek the dead on behalf of the living? To the law and to the testimony! If they do not speak according to this word, it is because there is no light in them” (Isaiah 8:19,20). The alternative to seeking mediums and psychics for counsel is to seek God the Creator of the heavens and the earth.
For more on what the Bible teach about the state of the dead, check the following link: https://bibleask.org/bible-answers/112-the-intermediate-state/
In His service,