Here's one of my weekly Show-Off features of my personal photography on The Travel Photographer's blog. Click on the photograph to view it larger size.
I took this photograph of a renunciate at the Sufi shrine of Nizzam-Uddin in Delhi. This is the mausoleum of Delhi's most famous Sufi saint Nizamuddin Auliya, and is visited by thousands of Muslims, and sees a large share of Hindus and Christians, on a daily basis.
I hesitate to describe this man as a sadhu, although that is the popular name for Indian ascetics, since in this case, I'm not sure of his religion. He seems to live at the Sufi shrine, however the heavy chains and padlocks around his neck reveal that he practices self-mortification, which is frowned upon in Islamic theology. I had met another individual at the shrine who told me that he wore a vest made of chains and padlocks as penitence for the sins of mankind, and who professed that he was following the teachings of Islam.
Although Sufism originates from the philosophy adopted by early Muslim ascetics, none of those practiced self-mortification of that kind. It may be that this ascetic's a follower of a lesser-known sect (at least to me), or may have combined the ascetic practices of Hindu sadhus and those of the Sufis.