(salam) Such information forwarded to the general public tends to confuse the public, who then lose confidence in the leadership. It is best to first research the mas'ala and write an informed piece of advice. Below I copy the answer of Syed Muhammad Rizvi, of Toronto. I am sure even more research can be carried out. ANSWER: Salaamun `alaykum. You have asked about rennet derived from the animal which was not killed in Islamic way (zabiha). I had written an article in 1989 and will just summarize the relevant parts in answer to your question: Rennet or renin is tahir (pak) and halal even if it is obtained from the stomach of an animal which has not been slaughtered Islamically. An animal not slaughtered Islamically is known as maytah. Maytah is one of the `ayn najis (inherently unclean) things, so how can rennet extracted from a maytah be considered tahir? It is true that maytah is considered `ayn najis, but our mujtahids unanimously have declared that certain parts of the maytah are exempted from the najasat and are to be considered tahir. One of such parts of a maytah is rennet, known in Arabic as anfaha or minfaha. (See al-Khu'i, Minhaju 's-Salihiyn, vol. 1, p. 109; masala No. 393 in the chap. on taharat. This is also in the new edition of as-Sistani. For the view of other mujtahids of our time, see Sayyid Kazim al-Yazdi at-Tabatabai, al-`Urwatu 'l-Wuthqa, p. 20-21.) Not only is the anfaha considered tahir, it is also considered halal. (See Minhaj, vol. 2, p. 336; masalah No. 1691 in the chap. on food and drink.) This is not a new fatwa or a new mas`alah; our Imams (a.s.) have given clear guidance on this issue in quite a few ahadith. I will just quote some parts of a conversation between Qatadah and Imam Muhammad al-Baqir (a.s.). Qatadah: Tell me (the law) about cheese. Imam (a.s.): There is no problem in it. Qatadah: But sometimes the anfaha (rennet) from a maytah is put into it. Imam (a.s.): Still there is no problem in it because there are no veins in it nor any blood or bones; it comes out from between the intenstine and the blood vessels. The case of anfaha is similar to that of an egg which comes out of a dead chicken. Would you eat that egg? Qatadah: No; nor would I tell others to eat it. Imam (a.s.) And why is that? Qatadah: Because the egg is from a maytah. Imam (a.s.): But if you hatch that same egg and a chicken comes out of it, would you eat it? Qatadah: Yes. Imam (a.s.): "Now, what has made the egg haram for you but made the chicken halal for you?! Similarly, the anfaha is like the egg [from the maytah but halal]..." (Wasa'ilu 'sh-Shi`ah, vol. 16, p. 364) Yours in Islam, Sayyid M. Rizvi