When Muslims migrate to foreign countries to reside in the midst of non-Muslim communities, they are faced with problems in eating and drinking because they don’t find foods that are familiar and desirable to them, nor are their ingredients known to them...
Buying Meat from a Muslim
A Muslim is allowed to buy all kinds of halal meat from a Muslim shopkeeper who sells it to Muslims. Such meat would be considered halal even if the vendor belongs to a school of thought which have different conditions for slaughtering from ours as long as there is a possibility that the animal was slaughtered in accordance with our conditions.
If a Muslim knows and is sure that this meat is from an animal which is permissible for Muslims to eat (like cow, sheep or chicken) but that it is not slaughtered in accordance with Islamic laws, that meat is to be considered mayta.
Mayta is not permissible for a Muslim to eat even if its seller is a Muslim. Similarly, such meat is impure (najis) and would make other things impure, if it comes into wet contact with it.
Buying Meat from a Non-Muslim
If a Muslim buys or receives meat from a non-Muslim, or from a Muslim who got it from a non-Muslim and did not inquire about its slaughtering according to Islamic laws, such meat is haram for him. But if the Muslim does not know that the animal was not slaughtered according to Islamic laws, it would not be considered najis, although it is still haram.
Fish
In order for fish to become permissible for a Muslim, it must have the following conditions:
a. The fish must have scales on it. [That is, it should not be a skin fish.]
b. The Muslim should be certain or satisfied that the fish has come out of the water alive or that it died while it was already in the fishing net.
It is not necessary for the fisherman to be a Muslim or to utter the name of Allah for the fish to become halal. So, if a non-Muslim catches a fish and brings it alive from the water or it dies after getting caught in his fishing net or fishing line, and it has scales on it, it is permissible to eat.
The second condition is fulfilled in almost all the countries, as they say, because the universal method in fishing ensures that the fish comes out of the water alive or they die after they are caught in the fishing net. Based on this, it is permissible to eat the fish that one gets from a non-Muslim just as one gets from a Muslim, irrespective of whether it is canned or uncanned.[1]
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[1] A code of practice for Muslims in the west (Eating and Drinking). According to verdicts of Ayatullah Sistani.