There are essentially two explanations among the Rishonim for the prohibition of bishul akum (food cooked by a gentile). The first is that it is in order to avoid impurity (ochel tame), i.e. non-kosher cooking. The other more popular explanation is that the prohibition is to avoid intermarriage (mishum chatanut). The intermarriage targeted by the prohibition is not just of the immediate kind, in other words, if there were no specific personal chance of intermarriage the prohibition still applies.
Because of this prohibition, usually a Jewish person has to be involved in the cooking process as well. This is usually done by at least lighting the fire, etc. (There are a few kinds of food that are exempted from this requirement). This creates a unique situation in which it becomes quite difficult to eat with our fellow gentile believers in their homes, no matter how strictly they keep the laws of kashrut. In addition, the primary reason for doing this is in order to avoid becoming too friendly with them. This social barrier is quite similar to the one that Kefa was instructed to overcome in Acts 10. He wasn’t asked to eat non-kosher food but to eat with those who until now were considered non-kosher to eat with.
However, there is a certain amount of truth to each explanation. Both the concern for eating non-kosher food and the desire to avoid becoming too friendly with the general gentile world are valid ones. We often assume gentile means “believer” and that it is perfectly safe to relate to all gentiles. However, originally it had more of the connotation of “non-believer”. Also, the right balance of contact with the other and of strengthening one’s calling by interaction with the same (the Jewish world) needs to be struck to avoid assimilation, not just in marriage but in loss of Torah observance.
The immediate concern for avoiding transgressing Torah mitzvot (i.e. kashrut) as found in the first explanation is always valid. However, sometimes long-term preventative measures implemented to avoid intermarriage may be overridden by other concerns. The overriding principle in this case involves the unity of “the body of Mashiach”. Often this overriding principle is mistaken in its application. It is often assumed that the mitzvot are overridden for the sake of this unity, instead of the true application which is that the distance between people groups is overridden (when it does not threaten the mitzvot) for the sake of unity.
This overriding principle also does not truly override the prohibition of bishul akum. What it essentially does is allows us to rule leniently according to the first opinion. When the guidelines of the unity of the body do not apply, then we revert to the standard explanation. For example, commercially produced products will still be required to follow the standard halachot whether owned by believers or not.
Now, in order to fulfill this principle it is not always necessary to technically negate the second reason of chatanut. In the case of gentiles who are fully knowledgeable of kashrut and whose integrity can be trusted, the reason of ochel tame is not valid. In addition, since they are quite observant, there is very little true difficulty of chatanut since they may easily be converted at any time. (Note, however, that we are overriding the universal application of the principle of chatanut and only applying it locally). Only because of our unique history, whether that be lack of a conversion process or difficulty going through standard giur programs, do we even posses the anomaly of these kinds of gentiles.
However, there are certain times where it might be necessary to rule leniently according to the ochel tame example because of this principle. In that case, as long as supervision sufficient to provide kosher food is provided, the food itself should not be prohibited.
However, there are several caveats. 1) This should only be done within the limited confines of community fellowship (therefore, even Christian owned food businesses must still keep bishul akum laws) and occasionally also within the wider community. 2) There should be almost no reason to permit in the case of non-believing gentiles. The only exception might be within outreach, or to honor certain individuals or family members. 3) Even in these cases, the supervision required would be thorough enough that it is not that difficult to then do what is needed to be involved in the cooking process. This should almost always be done. However, b'di'eved, their food is acceptable.
