Worship is not accepted when one eats unlawful sustenance

Question

If a morsel of unlawful sustenance goes down into the stomach, then none of that person’s worship will be accepted, his children too will be illegitimate, and the body built from unlawful sustenance will also go to Hell. Kindly inform us of the hadith reference, and we will be grateful.

Answer

That worship is not accepted when one eats unlawful sustenance — this much is correct; but the meaning of non-acceptance is that such worship does not merit reward from Allah Most High and the Real, Most High (Haqq Taʿala), is not pleased with it; it does not mean that the fard is not discharged.

Source: Fatawa Mahmudiyya

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