Ever looked around a synagogue and noticed the incredible array of people from different races wandering the aisles? Hard to believe we’ve got anything in common, let alone common ancestry and religion.

In the late ’90s, a study came out attempting to prove that kohanim (priests), no matter their facial or racial makeup, all descend from a common paternal ancestor. The geneticists involved collected DNA samples from hundreds of kohanim, and searched for common markers on the Y-chromosome. Incredibly, they found that over 98% of men with a family tradition of priesthood showed evidence of descent from the same great-great-great grandfather.1

Ashkenazim, Sephardim, Yemenites and Italians can trace their backgrounds back to the Jews of the ExodusI find it fascinating that Moses’ older brother, the biblical High Priest Aaron the kohen, lived some 3,300 years ago but bequeathed his genetic signature to these men. Ashkenazi, Sephardi, Yemenite and Italian kohanim can actually trace their backgrounds back to the Jews of the Exodus. And if modern science has given us the tools to prove common ancestry, isn’t the next obvious step to dedicate ourselves to our common purpose—G‑d’s Torah and mitzvot?

The Fidelity Gene

Recently, I came across a statistic that absolutely floored me. According to one Australian laboratory, nearly one-quarter of the DNA tests performed demonstrate the assumed father not to be the real biological parent. One quarter!

Contrast this sorry record with that of Jews throughout history. What would happen if a kohen’s wife committed adultery? The resulting illegitimate child would be an assumed kohen. He’d join his “father” on the dais and recite the Priestly Blessing; he’d get dibs on the first aliyah. He’d hand down a tradition of priesthood to his own sons . . . But in reality he’s no kohen, and his DNA and that of his future male descendents would not bear those crucial markers.

But almost 100% of all men with family tradition of priesthood do descend from kohanim. Generation after generation of Jewish women were faithful to their husbands and their tradition. What a proud record of fidelity. Geneticists describe these results as “the highest record of paternity-certainty ever recorded,” and there is no reason to assume that their sisters married to Levites and Israelites were any less faithful to their spouses and religion.

Geneticists describe these results as “the highest record of paternity-certainty ever recorded”This devotion to our spouses and our G‑d has always been the way of the Jew. Even during our slavery in Egypt, subject to the capricious demands of an evil nation, our women distinguished themselves. The Book of Leviticus2 records the only example of illegitimacy, the product of the rape of a Jewess by an Egyptian overseer. The Torah hints that this woman’s flirtatious manner may have precipitated the dreadful occurrence, but the crime was committed by the Egyptian.

This sad exception only demonstrates how refreshingly modest and chaste were all other Jews. The very worst and most unfortunate incident of all the time they were in slavery was not a case of adultery, G‑d forbid, but abuse. It is to the credit of our ancestors that, no matter the temptations, irrespective of the dangers, they fought to stay faithful, and almost without exception they succeeded. This proud heritage they vouchsafed to us.

Jewish marriages throughout history are a model for all humanity, and the oaths and bonds that unite us with our partners and Creator will remain firm and unwavering for now and eternity.