I'm reaching, here, Mbo, but.....in Roman mythology, the spirits of the dead were called shades (one meaning of shade in the dictionary is ghost), and Hades was euphemistically called shades (plural construed as singular). The lyrics you posted seem to refer at least partly to a dead man, so there's a bit of a fit there. Gloria is a little more troubling, but I would speculate it is an attempt to approximate heaven, thus making the phrase "shades of gloria" mean "spirits of the good afterlife" more than "spectres of the underworld".

I suspect only the songwriter knows for sure.