Symbolism, Imagery, Allegory
Follow the, follow the, follow the, follow the, follow the yellow-brick road. Oh, wait, that's a different book. But Harry does use the idea of a golden road to explain certain moments in his life when he feels at peace. And believe us, for a guy like Harry those moments are rare.
The first time he mentions the golden track he is explaining that every now and then he gets this special feeling:
I dropped all my defences and was afraid of nothing in the world. I accepted all things and to all things I gave up my heart. […] Sometimes for a minute or two I saw it clearly, threading my life like a divine and golden track. But nearly always it was blurred in dirt and dust. Then again it gleamed out in golden sparks as though never to be lost again and yet was soon quite lost once more. (7)
The golden track seems to be a path to enlightenment that beckons Harry to follow it, but he can't hold onto it. It's like the path has been grown over because it hasn't been used.
This image of the golden track will zing right back into Harry's mind the day he finds the door to the Magic Theater. The colored lights reflecting on the wet ground, calling to him, remind him of the golden track:
But while I waited, thinking how prettily the letters had danced in their ghostly fashion over the damp wall and the black sheen of the asphalt, a fragment of my former thoughts came suddenly to my mind; the similarity to the track of shining gold which suddenly vanishes and cannot be found. (11)
Since Harry has already had those fleeting experiences of being at one with the world, he recognizes that the Magic Theater, with its glittering lights, might be one way to get back to that feeling.
He says that he "was freezing and walked on following that track in my dreams, longing too for that doorway to an enchanted theater, which was for madmen only" (12). Now we know that the path, which he had only caught glimpses of before, is a special track for Harry to find the magic.
Even though he hasn't yet found the way into the theater, just having a glimpse of the entrance is enough to really get Harry into a good mood. He is back into his happy place, and thinks,
The golden trail was blazed and I was reminded of the eternal, and of Mozart, and the stars. For an hour I could breathe once more and live and face existence, without the need to suffer torment, fear, or shame. (17)
Obviously, the trail is a sign that Harry is about to go somewhere, and as we read we'll figure out that his path is one to enlightenment, where he can feel free of suffering—not for fifteen minutes or an hour—but always.