Purity: Methods for Establishing the Kurr Quantity of Water

Practical Laws of Islam as per the teachings of Ayatullah Sistani

Ruling 22

There are two ways to establish that a quantity of water is kurr:

1. one is certain (i.e. he has yaqīn) or confident (i.e. he has iṭmiʾnān) about it, even if that is because of what someone has said;

2. two dutiful (ʿādil) men report it as so. If one dutiful or trustworthy person, or someone who has possession of the kurr water, reports it as so but his report does not give one confidence as to it being true, then based on obligatory precaution (al‑iḥtiyāṭ al‑wājib), the water being kurr will not be established.

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