Do All Fish with Scales Have Fins? A Fascinating Torah Insight and Scientific Question

The identifying signs of fish that are permitted for consumption are clearly stated in the Written Torah: “These you may eat of all that are in the waters: anything that has fins and scales you may eat” (Deuteronomy 14:9).

In the Oral Torah, we are taught an additional principle (Mishnah, Niddah 6:9): “Any creature that has scales also has fins; but there are those that have fins and do not have scales.”

A Remarkable Natural Principle

The Giver of the Torah reveals here a law of nature embedded in creation: any fish or aquatic creature that has scales must also have fins. However, the reverse is not necessarily true — having fins does not guarantee the presence of scales.

This has practical implications. If, for example, we find pieces of fish in a market that cannot be identified by species, but the skin is clearly covered with scales, then those pieces are permitted to eat, even if we did not see whether the fish had fins when it was whole.

This is because based on the presence of scales, we know with certainty that it must also have had fins, just as the Torah teaches. On the other hand, a fish that has fins does not necessarily have scales, and therefore would not automatically be permitted.

A Question for Modern Science

Now consider this: even in our time, after the discovery and study of hundreds and thousands of previously unknown species of fish and aquatic life, is there any scientist — no matter how renowned, who would dare to declare such a sweeping rule? Would anyone make such an absolute statement with complete certainty?

A Timeless Tradition

The Oral Torah was written down about two thousand years ago, yet it confidently presents this principle. The sages received it as part of the transmitted tradition, passed down from generation to generation all the way back to Moses, who received it from the Creator of the world.

It is therefore not surprising that all fish and aquatic creatures — both those known in the past and those discovered up to this very day, conform to this rule, without exception.

Who could have known this with such certainty, if not the Creator Himself?