If a person cannot find water, is it better for him to delay his prayer or to pray at the beginning of the time?
Question

                Is it better for a person who cannot find water to delay his prayer until the end of the time, hoping to find water, or to do tayammum and pray at the beginning of the time?
Praise be to Allah.
    That depends. It is preferable to delay the prayer until the 
    end of the time in two cases: 

    1 – If he knows that he will find water, then it is 
    preferable to delay the prayer, although it was not said that this is 
    obligatory, because there is no certainty that he will find water.  

    2 – If he thinks it most likely that he will find water, then 
    he should delay the prayer, because by doing so he is maintaining one of the 
    necessary conditions of the prayer, which is purifying oneself with water, 
    whereas praying at the beginning of the time is maintaining one of its 
    virtues only. 

    In this case, delaying the prayer and purifying oneself with 
    water is preferable. 

    Secondly, it is preferable to do the prayer at the beginning 
    of the time in three cases: 

    1 – If he knows that he will not be able to find any water.

    2 – If he thinks it most likely that he will not be able to 
    find any water.

    3 – If he is uncertain and is not sure in either case.