Are Martyrs Washed and Shrouded in Islam?
Question

If a Mujahid who is fighting for the sake of Allah dies, should we wash him and shroud him, or bury him in his clothes?
Praise be to Allah.The Martyr’s Burial According to Islamic Teachings
If the martyr dies in battle, he should not be washed or shrouded. This is the view of the majority of scholars, because of the Hadith of Jabir ibn `Abdullah (may Allah be pleased with him), who said that the Prophet (peace and blessings of Allah be upon him) issued orders that the martyrs of Uhud should be buried with their blood and not washed. (Narrated by Al-Bukhari, 1346)
Why Are Martyrs Not Washed
Rather they should not be washed, so that the traces of their martyrdom will be left on them. It was narrated that the Prophet (peace and blessings of Allah be upon him) said: “By the One in Whose hand is my soul, no one is wounded for the sake of Allah – and Allah knows best who is wounded for His sake – but on the Day of Resurrection he will come with a colour like the colour of blood and a fragrance like the fragrance of musk.” (Narrated by Al-Bukhari, 2803 and Muslim, 1876)
`Abdullah ibn Tha`labah (may Allah be pleased with him) narrated that the Prophet (peace and blessings of Allah be upon him) said: “Leave them with their blood, for there is no wound incurred for the sake of Allah, but he will come on the Day of Resurrection bleeding with a colour like the colour of blood but its fragrance will be like the fragrance of musk.” (Narrated by An-Nasa’i; classed as authentic by Al-Albani in Sahih Al-Jami`, 3573) (See Al-Mughni ma`a Ash-Sharh Al-Kabir, 2/333; Al-Maswu`ah Al-Fiqhiyyah, 26/274)
Views on Washing Martyrs in a State of Impurity
If the martyr was in a state of major impurity following sexual activity, the scholars differed as to whether he should be washed. The more correct view is that he should not be washed because there is no difference between one who is in a state of major impurity and one who is not. The Prophet (peace and blessings of Allah be upon him) did not wash those who were killed at Uhud. Moreover martyrdom is an expiation for everything.
The Washing of `Abdullah ibn Handhalah
With regard to the report that `Abdullah ibn Handhalah (may Allah be pleased with him) was washed by the angels, even if it is sound, it does not prove that the martyr should be washed by human beings, because the angels’ washing him is not something that is visible to us. The rulings for human beings cannot be compared to the rulings for the angels. What happened to Handhalah (may Allah be pleased with him) was by way of honouring him, not by way of enjoining anything upon us. (End quote from Ash-Sharh Al-Mumti`, 5/365)
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And Allah knows best.