By David Sedaca
To answer this question, one needs to understand a few other related questions. In the first place, what does it mean to “keep kosher”?
Keeping kosher refers to a set of dietary laws practiced by religious Jews, commonly known as kashrut. The state of being kosher or “keeping kosher” means that the individual adheres to the whole set of Jewish dietary laws.
In Ganzeh Galus’ Jewish Revival In The Deep Diaspora  we read what it means for a modern Jewish person to keep kosher.
“What is keeping kosher? Keeping kosher means eating only kosher foods. For traditional Jews it is a central part of the halacha’s (Jewish law) system of bringing God and God’s rituals and laws into every aspect of life. Some Jews also find it a way of connecting to their people as it is a peculiar ritual shared by Jews of many places for over two millennia; an alternative to more disruptive obsessive/compulsive rituals; a convenient way to drive friends and relatives crazy; or a suitable forum for one-upsmanship.”
The contemporary Jewish philosopher Yeshiyahu Leibowitz insists that any of the latter motives invalidate kashrut: one is keeping kosher only if one eats kosher food solely in order to fulfill God’s commandment and not for any other reason. Leibowitz’s view follows the teachings here of the great Jewish Spanish rabbi Maimonides, who says that the more tempting bacon is the more valuable avoiding it is.
Others disagree, contending that one ought to train oneself not to desire non-kosher food, or that motive is altogether irrelevant. Since only Jews are commanded to keep kosher, most authorities agree that there is no merit in non-Jews keeping kosher.
What makes kosher food different?
Kashrut (keeping kosher) is in large part a series of limits on meat eating. According to the Bible, human beings were strictly vegetarian from the creation of Adam and Eve until after the Flood (Gen. 1:29). Later, the Bible states that people were given permission to eat meat, but with restrictions, most of which apply only to Jewish people. These biblical restrictions form the foundations for the rules of kashrut, although many of the rules appear in recognizable form only in the Talmud.
According to Rabbi Kook, one of the main rabbis of Israel, kosher meat is God’s compromise form of vegetarianism – a second best for those who find it too difficult to live as Adam and Eve did in Eden. Rabbi Kook, accordingly, viewed vegetarianism as the highest form of kashrut and did not eat meat at all. Other authorities view the kosher rules as a way of remembering Jewishness and thinking about God in every aspect of life and thus see eating kosher meat as a special way to show adherence to God’s laws.
As it refers to eating meat, there are three main requirements found in the Scriptures:
- Ban on blood and torn limbs
- Restrictions on permitted species
- Ritual slaughtering
But just as Judaism has changed since the time of Jesus (today there is no Temple, no priests and no sacrifices) so did the interpretation and practice of kashrut. It is the Talmud, the corpus of Jewish oral teachings that was finally put into writing in the Mishna between the 2nd and 5th centuries AD, which adds a number of regulations to the biblical precepts.
One of these additional interpretations of “keeping kosher” is the separation of dairy products from meats. There is no evidence that this regulation existed during the time of the First and Second Temple, but it has become part of “keeping kosher” since Talmudic times.
Another issue that we must consider in trying to answer whether Jesus kept kosher is the fact that Judaism today is not the Judaism that Jesus lived. Whereas today keeping kosher is an option for most Jews and a way of life for Orthodox Jews, there was no option during Jesus’ time; they all kept kosher.
There were exceptions, for instance, those who chose a Greek or Roman lifestyle because it was convenient or fashionable. But there is no doubt that Jesus lived as a Jew, thus fulfilling the obligation of every Jew. He did “keep kosher” and the same can be said for His disciples.