In the world there are two things that serve as guides to a weary traveller on a lonesome journey in a pitch dark night; to wit, Sound and Light. These are the two aids also on the Path of Spirituality. Each of them has its own purpose.We have the divine Light in us and from within it emanates Sound, and the two together have been described  as FlamingSound or Sounding Flame.

All life and all power come from it. From the sun to the candle flame, all light comes from this grand powerhouse. The energy of the scientist and the pranas of the yogins are butmanifestations of this life-stream which, like electricity in the air, is all-pervading and allpowerful.

All the Prophets of the East and the West,who practiced the process of inversion and recession
or withdrawal of the soul current at will, speak of both the experiences of Light and Sound.
(Sant Kirpal Singh)

First the murmuring sounds resembling those of the waves of the ocean, the fall of rain,
and then running rivulets, after which the bhervi will be heard, intermingled with the
sounds of bell and conch.
(Nad Bind Upanishad, Hinduism)

How sweetly mysterious is the Transcendental
Sound of Avalokiteshvara!
It is the pure Brahman Sound. It is the subdued
murmur of the sea-tide setting inward. Its mysterious
Sound brings liberation and peace to all sentient
beings who in their distress are calling for aid;
it brings a sense of permanency to those who are
truly seeking the attainment of Nirvana’s Peace.
(Surangama Sutra, Buddhism)

Hearing the Sound resembling that of the conch
and witnessing the Lotus Light like that of a newly
blossomed flower between the two eyebrows,
One faces his Ishta, the Satguru.
(Suttagame, Jainism)

Hundreds of moons and thousands of suns
may illumine the world,
But without a Master-soul, they fail miserably
to dispel the darkness of the human mind.
Without contact with Shabd, one remains
stark blind and deaf,
Of what avail is their life in this world?
They get not the Water of Life and escape
not the endless cycle of births.
(Guru Amar Das, Sikhism)