“To the angel of the church in Sardis write:
These are the words of him who holds the seven spirits of God and the seven stars. I know your deeds; you have a reputation of being alive, but you are dead. 2 Wake up! Strengthen what remains and is about to die, for I have found your deeds unfinished in the sight of my God. 3 Remember, therefore, what you have received and heard; hold it fast, and repent. But if you do not wake up, I will come like a thief, and you will not know at what time I will come to you.
This link at davidschrock.com gives several interpretations about what Jesus may mean by "the seven spirits of God" in this verse, referencing verses of prophecy in Isaiah 11:1-5. The writer notes that the seven qualities in Isaiah 11:2 are described as the "sevenfold spirit of God".
