Hazrat Ata says that if a person performs tayammum and offers prayer, and then finds water within the time of that prayer, he should offer the prayer again.

Hazrat Muhammad bin Abdur Rahman says that if a person performs tayammum and offers prayer, and then during the time of prayer he finds water, he should offer the prayer again.

Hasan says that if a person performs tayammum and offers prayer, and then finds water within the time of that prayer, he should offer the prayer again.

Hazrat Zuhri says that if a person performs tayammum and offers prayer, and then finds water within the time of that prayer, he should repeat the prayer.

Hazrat Ata says that two men became junub (in a state requiring ritual purification). Both performed tayammum and offered prayer. Later, both found water within the prayer time. One of them repeated the prayer, while the other was content with his previous prayer. This was mentioned to the Prophet (peace and blessings be upon him), and he said: The one who repeated the prayer will have double reward, and the other's prayer is also valid.

Hazrat Ali (may Allah be pleased with him) says that a person should wait until the last time for prayer; if he finds water, he should perform ablution, and if he does not find water, he should perform tayammum and offer the prayer. If he finds water after offering the prayer, he should perform ghusl but should not repeat the prayer.

Hazrat Abu Salamah says that he will not repeat the prayer.

Hazrat Ibn Umar (may Allah be pleased with them both) narrates that if a person performed tayammum, then offered prayer, and then entered the city during the time of prayer, he will not repeat the prayer.

Ibrahim says that when a person performed tayammum and offered prayer, and after completing the prayer he found water, then he has completed his prayer.

Hazrat Mujahid says that he will not repeat the prayer; his prayer is valid.