Vibhuti (sacred ash) is very important in certain traditions of Hinduism. First of all, it is usefully produced from ritually important sources, such as Yagnya fires, a sadhu’s Dhuni fire, burnt cow dung (a holy substance), or even cremated bodies in Aghora or Vamachara Tantra. Vibhuti is called for in certain rituals, and tens of millions of Hindus - mainly Shaivas - apply Vibhuti to certain parts of their body every day while reciting certain mantras. Even more Hindus, probably hundreds of millions, keep at least a small supply of Vibhuti at their home altar among their puja supplies, and may apply it to their Murti (idol of their beloved Ishwara).
The Shiva Mahapurana praises the importance of Vibhuti very highly. It says that each individual particle of ash which clings to the skin when Vibhuti is applied to the forehead is to be considered an individual Shiva Lingam; that Vibhuti purifies and elevates the devotee of Shiva, and makes one’s works more fruitful.
Vibhuti is often provided at Hindu temples for visitors to put on, and packets of Vibhuti are very commonly given to participants after certain Hindu rituals, considered intensely sacred. One common such ritual is the Vibhuti Abhishekam of the Shiva Linga:
