Why is a deceased person washed?
The washing is not done for the sake of the body itself, but out of respect for the deceased and consideration for the living, and because Islam places great value on cleanliness. Martyrs who fall in battle are, as a rule, not washed.
After death the soul leaves the body, and the body decays. So one might ask why it is washed at all. The answer is that the washing does not serve the body as such. It serves human values, and these concern both the deceased and the living.
First, it is a sign of respect for the deceased. He should be taken to the grave clean, cared for and fragrant. A body left untended can smell so strongly that even the most loving relatives draw back. That would not do justice to human dignity. Someone who is washed and buried with honour leaves a good memory behind.
At the same time, the washing is done out of consideration for those left behind. Their love for the deceased needs a way to be expressed. When they wash him and carefully prepare him for burial, they can do him one last service.
Finally, Islam places great value on cleanliness in general, more than many other teachings. The verse above says that God loves those who purify themselves. It is in keeping with this principle that a person should be clean on his final journey as well.
Martyrs who fall in battle are, as a rule, not washed. Their bodies are often so badly injured that washing would hasten decay rather than check it. They are therefore laid in the grave without further treatment. The Holy Qur’an says of them that they should not be called dead.