The number seven is often used in the Scriptures, which signifies perfection or completeness. The seven spirits might conceivably refer to a group of angelic beings. But …
The Revelation of John
The Book of Revelation is the final book of the New Testament, and consequently is also the final book of the Christian Bible. Its title is derived from the first word of the Koine Greek text: apokalypsis, meaning "unveiling" or "revelation." John authored this book on the island of Patmos about 96 C.E.