Ancestry test for Christmas? Why some people are converting to Judaism

A surprising new trend has occurred in recent years in an unexpected intersection between faith and biology: a rise in conversion to Judaism thanks to DNA tests.

Judaism is not a missionary faith. It believes that there are many paths to heaven and it does not particularly matter which one you take. To put it another way: so long as you are a good Jew or a good Christian, Muslim, Hindu, Buddhist, agnostic or atheist, that is sufficient. It is the 'good' bit that counts: what you believe is personal and variable, but what you do and how you interact with others is what matters.

This is not a modern approach, but goes back to the second century, when the rabbis declared 'the righteous of all nations have a place in the world to come'. Jews, therefore, are largely Jews by birth – born into a Jewish family and acquiring Jewish identity and values as they grow up.

However, Judaism is open to converts if they ask to join the faith. This goes back to the Bible and the famous line in the Book of Ruth 'Your people shall be my people, and your God my God'.

Until very recently, the vast majority of converts have been those who have married someone Jewish and converted either because, having been introduced to Judaism, felt they wanted to adopt it for themselves; or they have done so to unify the household faith and provide a single faith background in which to bring up any children.

What has changed is the new popularity of online DNA tests, often purporting to identify somebody's ancestry, which has led people to discover they have Jewish ancestry. In most cases, this came as a total surprise. They were not looking for a particular result, nor had they even initiated the test themselves, but had been given it by a friend as a birthday or Christmas present.

For some people, this discovery is just a matter of historical interest and they leave it at that. Just because they find an ancestor was a pirate does not means they suddenly feel impelled to set sail for the high seas and attack a galleon laden with gold. For others, though, it awakens a desire to pursue what they regard as their religious heritage. In Martin's case (not his real name, but a situation very typical of many others) it was his paternal-great grandfather who had been Jewish, but the knowledge had been lost.

This may sound surprising in such a relatively short time-span. However, the great grandfather had married someone non-Jewish, and his family had cut him off for marrying out of the faith, while her family had not advertised the fact and the two of them had brought up their children as 'ordinary people' and not told them of his background.

In other instances, the lineage can go back not just a few generations, but centuries. In a significant number of cases it dates to 1492 when the family had been living in Spain and all Jews had been expelled from the kingdom. The only way Jews who wanted to remain could do so was by converting to Catholicism but secretly keeping their Jewish identity. Eventually, though, that awareness became so diluted that it faded from memory.

In both scenarios, the DNA results have led the individuals concerned to explore their Jewish heritage and decide to re-adopt them. Of course, there has also been the wider interest in one's origins since 2007 and the BBC's long running programme Who Do You Think You Are?. The trend may be even earlier than that, starting in 1977 with the American television series Roots, also shown in England, based on Alex Haley's novel of the same name published a year earlier.

For some people, discovering they have a lost heritage, especially one with a strong sense of community, is far better than having the amorphous identity of being English and lapsed Church of England (or a 'nothing').

However, the DNA test by itself does not confer Jewish identity. Judaism is not just about the bloodline, but also being engaged in the practices of the faith, involved in communal life and having the knowledge to feel at home in being Jewish. Assuming the person belonged to another faith up to that point or, more likely, had no faith, they need to formally convert to Judaism.

The process for conversion is lengthy, for Judaism is often described as a 'way of life' rather than just a faith. So becoming Jewish means learning not only about the beliefs, but also how to do Jewish rituals, particularly as many take place in the home. It means that the conversion usually takes a minimum of a year, in order to experience the cycle of the festivals.

This usually takes the format of a weekly or fortnightly class, led by the rabbi or a qualified teacher. It also involves learning Hebrew, so as to be able to join in the services (Orthodox ones are entirely in Hebrew, Progressive ones are an equal mix of Hebrew and of English). Judaism is very much a communal religion, sharing ceremonies with others, so the person is expected to join in some of the social, cultural and other activities too. At the end of the process, they attend the Beit Din/Rabbinic for a conversation with a panel of other rabbis, to check both their sincerity and knowledge, after which they are formally granted Jewish status.

Tuition and community involvement takes place in a person's local synagogue, but they then come to the Beit Din (the Rabbinic Court which deals with status issues, of which I am the Reform Convenor in the UK) for an interview and the conversion to be registered.

As DNA tests have become the go-to gift for someone whom you don't know what to get, it is rather ironic that a Christmas present could lead them to become Jewish.