I thought it was about smoking dope, you know, Mary Jane Wanna.
In those decades everything was supposed to be a veiled drug reference.
Only recently I learned the true story of Crystal Blue Persuasion by Tommy James. Several music sites still conclude without any evidence it meant a drug haze.
James said it was about the Bible’s description of the Hebrews’ experience of the Presence of God in the Temple.
He was inspired by his reading of the book of Ezekiel where it speaks of the Blue Shekinah Light which represented the presence of the Almighty God and the Books of Isaiah and Revelation where it speaks of a bright future of a brotherhood of mankind living in peace and harmony.