Najis

Consider this:

Najis Things
Issue 84: * The following ten things are essentially najis:
• Urine
• Faeces
• Semen
• Dead body
• Blood
• Dog
• Pig
• Kafir

Najis?

In Islamic law, najis are things or persons regarded as ritually unclean. According to Islam, there are two kinds of najis: the essential najis which cannot be cleaned and the unessential najis which become najis while in contact with another najis.  Contact with najis things brings a Muslim into a state of ritual impurity (in opposition to ṭahārah, ritual purity). 

Kafir?

Najis things » Kafir
107. An infidel i.e. a person who does not believe in Allah and His Oneness, is najis. Similarly, Ghulat who believe in any of the holy twelve Imams as God, or that they are incarnations of God, and Khawarij and Nawasib who express enmity towards th e holy Imams, are also najis. And similar is the case of those who deny Prophethood, or any of the necessary laws of Islam, like, namaz and fasting, which are believed by the Muslims as a part of Islam, and which they also know as such. As regards the people of the Book (i.e. the Jews and the Christians) who do not accept the Prophethood of Prophet Muhammad bin Abdullah (Peace be upon him and his progeny), they are commonly considered najis, but it is not improbable that they are Pak. Ho wever, it is better to avoid them.

108. The entire body of a Kafir, including his hair and nails, and all liquid substances of his body, are najis.

109. If the parents, paternal grandmother and paternal grandfather of a minor child are all kafir, that child is najis, except when he is intelligent enough, and professes Islam. When, even one person from his parents or grandparents is a Muslim, the child is Pak (The details will be explained in rule 217)...

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