Must a person repeat the prayer if they performed Tayammum based on a presumed fear that turned out to be baseless?
Chapter on Tayammum
Al-Mughni
Book of Purification
Primary text
If a person's fear was based on an assumption that proved false—such as mistaking a dark object for an enemy at night, or a dog for a lion or leopard—and he performed Tayammum and prayed, there are two views on whether he must repeat the prayer. The first view states that he does not need to repeat the prayer because he performed what he was commanded to do based on the apparent situation, thus fulfilling his obligation.
Supporting text
The second view mandates repetition because he performed Tayammum without a legitimate cause, making it similar to one who assumed he forgot water when it was actually with him.