Is it permissible to pray in impure clothes out of necessity (such as the clothes on which some urine drops have fallen, sperm has fallen) when one cannot change his clothes or by doing so he will miss the prayer? Please answer in detail.

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

Mani (sperm) is pure according to the majority of the Muslim scholars even though removing its stains from the clothes is better in order to keep the cleanliness than leaving it. ‘Aa’shah the mother of the believers, used to remove the sperm from the clothes of the Prophet .

As for washing urine stains from the body and the clothes, it is obligatory. 

Therefore, a person should take all precautions in order to avoid becoming impure by drops of urine, by seeking a suitable place and adopting proper ways for relieving oneself.

The Prophet said: “Keep away from urine since most torment of the grave is due to not avoiding urine.” [Al-Daruqutni, Sheikh al-Albani considered it as sound].

In brief, washing the urine from the body and clothes is compulsory if it is much.  If it is only in a little quantity, then some scholars from the Shaafi’i, Maaliki and Hanafi Schools are of the opinion that such a small quantity is tolerable and washing it is not compulsory. They have different opinions in determining the amount that is considered as small and when it reaches the amount that is considered as much, it should then be washed.  The Maaliki School is of the opinion that if a fly leaves some stains of urine or feces which are not noticeable and to avoid that is very hard for people, then such a quantity is considered little and is tolerable. The Hanafi School is of the opinion that if the quantity does not exceed the size of a Dirham, then it is tolerable.

Some other scholars, like those of the Hanbali School, are of the opinion that there is no difference between a small and a large amount of impurity as far as the matter of purity is concerned except if it is so small that it is not noticeable, such as some trace of blood on one’s clothes which could be excused.

The opinion of the Hanbali School is the preponderant one since there is no evidence that supports the first opinion. Also, there is no evidence that can be used as criterion to determine the small quantity.

Therefore, if one’s clothes become impure, one has to remove the impurity regardless of the quantity.  If one cannot remove it and the time of the prayer is about to end, then one may perform the prayer in those clothes since Allah does not burden a soul beyond its scope.

Allah Knows best.