as a substitute for both forms of purification, and the limbs involved are the same in both forms of purification.

With regard to continuity, it is even more appropriate to say that it is obligatory in both forms of purification, for it would be far-fetched to say to someone who wiped his face at the beginning of the morning and his hands at noon: “This is the prescribed manner of tayammum!”

Intention is required for that on account of which one performs tayammum, whether ritual impurity or something else.

His statement, “Intention is required”: a condition, in the linguistic sense, is a sign. This is seen in the saying of Allah, Exalted is He: “Are they only waiting for the Hour to come upon them suddenly? Yet its signs have already come.” [Muhammad 18] That is, its indications.

In the terminology of the legal theorists, it is that whose absence necessitates absence, while whose presence does not necessitate presence.

For example, wudu is a condition for the validity of prayer: its absence necessitates the absence of validity, but its presence does not necessitate the occurrence of prayer, for a person may perform wudu and not pray.

A cause is that whose presence necessitates the presence of its effect, and whose absence necessitates its absence. The difference between it and a condition is that the presence of a cause necessitates the presence of its effect, unlike a condition.

An impediment is that whose presence necessitates absence, while whose absence does not necessitate presence—the opposite of a condition.

His statement, “intention”: it has been discussed previously. (1)

His statement, “for that on account of which one performs tayammum, whether ritual impurity or something else”: the phrase “whether ritual impurity” is connected to “one performs tayammum”; it is not explanatory of the pronoun in “for which,” because according to us