The respected and authoritative Encyclopedia Britannica has a startling account about what's behind Halloween:
"Halloween, in medieval times All Hallows Eve, a holy or hallowed evening observed on October 31, the eve of All Saints Day; in modern times, it is the occasion for pranks and for children requesting treats or threatening tricks."
"In ancient Britain and Ireland, the Celtic festival of Samhain was observed on October 31, the end of summer. The date was also the eve of the new year in both Celtic and Anglo-Saxon times and was the occasion for one of the ancient fire festivals when huge bonfires were set on hilltops to frighten away evil spirits. The date was connected with the return of herds from pasture, and laws and land tenures were renewed. The souls of the dead [see What Happens When You Die? and Where Is Your Soul?] were supposed to revisit their homes on this day, and the autumnal festival acquired sinister significance, with ghosts, witches, hobgoblins, black cats, fairies, and demons of all kinds said to be roaming about. It was the time to placate the supernatural powers controlling the processes of nature. In addition, Halloween was thought to be the most favorable time for divinations concerning marriage, luck, health and death. It was the only day on which the help of the devil was invoked for such purposes." (Encyclopedia Britannica, 15th Edition, volume 4, page 862)
And what does God's Word say about participating in activities based on paganism, witchcraft, demons, divination, and "seeking the help of the devil"? From the pages of The Bible:
Fact Finder: Does Satan himself masquerade as "an angel of light"?
2 Corinthians 11:14
See also -
That Old Serpent
Did God Create The Devil?
The Lame Duck
What Does Satan Look Like?
Could Satan Repent?
Why Demons Are Afraid Of You