Asalamalykum. 1) muslims can’t eat pig because the animal eats its own waste. However as fish live in water, do they also not consume their own waste? Why is fish acceptable & not pork? Jazzakullah!
In the Name of Allah, the Most Gracious, the Most Merciful.
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh.
Your assumption that swine is haram because they consume waste is incorrect. Swine is haram because of the express prohibition of Allah Ta‘ala. It is haram even if it does not consume waste. Thus, your analogy is incorrect.[1]
It is also incorrect to assume that fish consume their own waste because they live in water. Nevertheless, it is permissible to eat fish regardless of their eating habits because the shari‘a has permitted it.[2]
And Allah Ta‘ālā Knows Best.
Checked and Approved by:
Mufti Ebrahim Desai.
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[المائدة: 3]
{حُرِّمَتْ عَلَيْكُمُ الْمَيْتَةُ وَالدَّمُ وَلَحْمُ الْخِنْزِيرِ وَمَا أُهِلَّ لِغَيْرِ اللَّهِ بِهِ}
الدر المختار وحاشية ابن عابدين (رد المحتار) (٦/٣٠٦)
(قوله ولو متولدا في ماء نجس) فلا بأس بأكلها للحال لحله بالنص وكونه يتغذى بالنجاسة لا يمنع حله