purification cannot be attained. Thus, the proponent of this view merely says:

“It removes ritual impurity temporarily, until one is able to use water, whereupon the impurity returns.”

This is possible, not impossible. The revealed law has indicated this by making earth a means of purification. It can only be a means of purification if it removes ritual impurity; otherwise, while ritual impurity remains, it cannot be a means of purification.

As for someone who says, “It does not remove ritual impurity, but merely permits prayer, while ritual impurity remains the impediment to prayer”: if he means that it is a fully sufficient impediment, as it is when water is available, then he is mistaken. A fully sufficient impediment necessarily prevents prayer, whereas someone who has performed dry ablution is permitted to pray and is not prevented from doing so. Something cannot exist without that which necessarily follows from it. If, however, he means that the cause preventing prayer remains present but does not take effect because a legally prescribed purification has removed its prohibitive effect, and that this prohibitive effect returns once one becomes able to use water, then this is correct.

Likewise, if someone who says, “It removes ritual impurity,” means that it removes it just as water does, so that it cannot return without another cause arising, then he is mistaken. It is established by explicit scriptural text and consensus that once a person becomes able to use water, he must use it, even if no second state of major ritual impurity has arisen since the first. This is unlike purification with water.

But if he says, “By its removal, I mean the removal of the impediment’s prohibitive effect, so that it no longer prevents prayer until water becomes available,” then he is correct. There is no disagreement between the two positions concerning the practical rulings of the revealed law.