When I heard it, it made a strong impact on me, and the wording brought God to my mind. I would like to hear what others think of it, please.
I listened to it before, but since I didn't pay much attention to the lyrics, I didn't make any spiritual connection. Now that you mention it though...
*It seems to me that it speaks of someone who is ignorant of God (in darkness, his old friend), that receives a vision (a spiritual word, a ray of light) that leaves an imprint within his otherwise hardened heart that silences everything. The sound of silence is that inner deadening caused by spiritual insensitivity.
Under the dim light of human reasoning (street lamp), this life seems like a restless dream, without meaning and lonely. Until the neon light of the Gospel (or Christ) stabs our understanding and splits the night of our ignorance, and softens our heart with His touch.
In that neon light he can now see (with empathy) the people around him and their tragic condition. How, despite their outward interactions they are isolated and prisoners of their hardened hearts.
Fools, he says, hear my words and believe Christ, stretch your arms in prayer so that Christ can reach you (and give you hearts of flesh instead of stone), but his words, like silent raindrops, echo in their hardened hearts (wells) as if on deaf ears.
Instead the people bow and pray to the neon god they made. Nevertheless, the light of the Gospel still flashes and the words of the prophets are still proclaimed in subways and halls, whispering the truth, trying to break the sound of silence…
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* Each paragraph interprets the respective stanza.