Purity: Purification of Sole of Foot or Shoe Without Wetness

Practical Laws of Islam as per the teachings of Ayatullah Sistani

Ruling 180

It is not necessary for the impure sole of one’s foot or shoe to be wet – it becomes pure by walking even if it is dry.

-Ayatullah Sistani, Practical Laws of Islam, Purification (Taharah)