as an option. The narration that reads “awlahunna” (“the first of them”) is the weightier of the two, owing to the greater number of its transmitters, the fact that both of the two Imams included it, and because introducing earth in the very first washing renders the vessel cleaner.

What is derived from the ḥadith
1 A dog is impure, and every part of its body as well as all of its excretions are impure.
2 Its impurity is classified as a severe impurity; it is the most serious of filth.
3 Nothing removes that impurity and restores ritual purity except seven washings.
4 If a dog laps from a vessel, it is not enough merely to purify the leftover liquid; one must pour it out, then wash the vessel seven times, one of which is with earth.
5 The Prophet’s phrase “if it laps” excludes a case where what the dog touched with its tongue was solid, for the obligation is to discard whatever the dog’s mouth contacted, and the vessel need only be washed when moisture is present.
6 Using earth once among the seven washings is obligatory, and it is preferable that this be the first washing so that water follows it.
7 Only earth qualifies; no other cleansing agent may be substituted, for three reasons:
a) Earth achieves a level of purification that other cleansers do not.
b) Scientific studies have shown that only earth produces this specific cleansing effect—one of the scientific miracles of this Muḥammadan law; its Messenger spoke not from his own desire, but only by revelation.
c) Earth is what the text of the ḥadith explicitly stipulates; we are therefore bound by it. Had something else sufficed, the revelation would have mentioned it—“Your Lord is never forgetful” (Maryam 19:64).
8 Earth may be employed by pouring water over the earth, sprinkling earth onto the water, or using earth already mixed with water to wash the spot. Merely wiping the impurity with dry earth does not suffice.
9 Medical research, using magnifying instruments and modern microscopes, has established that in a dog’s saliva