If a specific count is required for impurities other than dog/pig filth, what is the prescribed number?
Chapter on what purification is achieved with regarding water
Al-Mughni
Book of Purification
Primary text
If the obligation for counting washings is affirmed for general impurities, there are two related narrations regarding the quantity. One suggests seven times, based on the general command mentioned previously. The second suggests three times, based on the Prophet's command to wash one's hand three times upon waking from sleep before putting it into a vessel, to dispel the doubt of impurity. The three washes are considered sufficient to remove the doubt of impurity.
Supporting text
It is also narrated that the requirement is three washes for the place of Istinja (due to repeated occurrence of impurity leading to leniency) and seven washes for all other places. This is supported by the allowance of three stones for Istinja, even though water is more effective at cleansing.