Inner Dust: What it is?

Excerpt from “Naam or Word”, by Kirpal Singh (p. 376)

In the Sikh scriptures It is described as Eternal and Everlasting Naam or Word — the Sound-current.
“Nanak prays for the Sadhu’s dust, It is the precious Naam of God.” – Dhanasri M.5
“I would like to make my hair a tasseled fly-drive for the Saints,
And bow in adoration unto them at the Til (still point in the body where His Radiant Form appears) and adorn my face with their Dust (light).” – Suhi M.5
This dust of Saints is in every one of us. We live by the Light of God within, technically known, as Charan Dhur or Dust of the Feet.
It has in it the Sound principle or the Harmony — the active life-principle that grants life everlasting.
The dust of the Lord’s feet is a peerless gift that one can pray for and seek. The gods and goddesses, Rishis and Munis long for it.
“I have adorned my forehead with the Dust of the Lord (Heaven’s Light)
Even the Rishis, Munis, and the gods are far removed from It.” – Dhanasri Namdev
In the ‘Dust of the Sadhus’ lies the merit of myriads of pilgrimages, fasts, and vigils and countless yogic disciplines.
“One can acquire the merit of myriads of pilgrimages and yogic practices if one is able to secure the gift of dust from a Sadhu (Inner Light).” — Sri Sag M.5
Alongside the “Dust of Saints’ feet”, we have references about the ‘Dust of Gur-sikhs’ feet’; that is of the true Sikhs or devoted disciples of the Master.
“The lowly Nanak asks for the dust of the devoted disciples of the Master (Gur-sikh)
Who himself practices the holy Word and instructs others to do the same.” – Gauri War M.4
This dust (Light and Sound of God) is an elixir of life that grants salvation – a life of bliss both here and hereafter.