Chilla (Persian: چله, Arabic: أربعين, both literally "forty"), also known as Chilla-nashini, is a spiritual practice of penance and solitude in Sufism known mostly in Indian and Persian traditions. In this ritual a mendicant or ascetic attempts to remain seated in a circle practicing meditation techniques without food for 40 days and nights in imitation of the Arba'een.[1][2]
The word chilla is derived from the Persian word chehel "forty".[3]
Chilla is commonly performed in a solitary cell called a chilla-khana.[4] The place itself is sometimes called Chilla where chilla has been performed.[4]
The most famous case of chilla is found in the biographies of the 14th century Sufi poet Hafez of Shiraz.[5][6][7]
A practice similar to chilla is also performed by Hindustani classical music practitioners at an advanced level. It is called chilla katna.