A Gift To My Father

My father is a Rabbi who has run the website Betemunah.org for many years. I think it actually started as an AOL page--I think he even still uses his AOL email account to this day. He and a friend did a very long research project to rediscover an old schedule for Bible readings.

Mainstream Orthodox Jews read the entire first five books of the Bible--called the Torah--once a year. The reading, called a Seder, is distributed weekly and done when Jews meet for worship on the Sabbath.

In addition to reading from the Torah, they also have readings from other passages in the Bible--they call the Tanach. These readings have some connection to the Torah readings, hence why they're read together. On top of that, anybody doing serious studying will also read material outside of the Bible, such as the Talmud and what not.

And you must be serious to even consider doing all this reading because it is a lot. Typically men studying to become Rabbis are the only ones capable of dedicating the time to do all that reading.

This Annual Cycle of reading the Torah is not the only one. In fact, it's the newer of the cycles. Previously, Jews read the Torah using a Triennial cycle where they read the full Torah over the course of three years. This cycle is still used today by Conservative Jews. It has the advantage that it allows more people to study together without people getting left behind by the grueling pace seen in the Annual Cycle.

There is a problem that my father and his friend found with the Triennial Cycle, however: it doesn't make a lot of sense. Readings from various parts of the Bible need to be coherent with the Torah readings, but my father and his friend believed that they also need to be coherent with the festival readings.

Jewish festivals have their own dedicated readings, whether you use the Annual or Triennial cycles. Getting readings to stay in-sync with the festival readings is important for understanding the full meaning of the readings since there is considerable context left out of the written words of the Bible, but still intended to be understood. Jews call this context the Oral Torah because it was originally banned from being written down and was passed down orally.

Over many years, my father and his friend rediscovered what they believe to the true original "Triennial" reading cycle--a 3 1/2 year reading cycle or what they call a Septennial Cycle because it is read in full twice every seven years. It took so long because records about the cycle a sparse and rare, and because the Hebrew calendar's rules are extremely complicated. That forced the discovery of a reading cycle that both is coherent both thematically by itself but also adheres to rules for the calendar.

The trouble is that my father's friend has passed away. My father is growing older and is the only one with a direct knowledge of the complex rules for calculating the readings and how/why they were derived. He can create a chart for a full Septennial cycle, but he has yet to be able to reliably teach others how to do so. If nothing changes, it is possible that the discoveries he and his friend made will be lost.

So the question is: if there are indeed rules, can't they simply be codified and passed on as software, making them accessible to anybody far into the future?

I believe so, and so I have set out to build an application that does just that--written in Almighty Common Lisp, of course.

My plan is to build both a web and native version of an application that has the following features:

1. Hebrew <-> Gregorian Date conversion.
2. Sabbath start/end times.
3. Reading search for any given date/Sabbath.
4. Chart generation.
5. Commentary/extra reading suggestions.

As I wrote in the previous article in this series, I believe native application development is going to be the trend going forward thanks to the power of LLMs. The advantage specifically for this project is that a native application in Lisp should (theoretically) be useable forever. You don't need to connect to a server (still maintained, right?). Just open the executable. If you need an executable for your new architecture, just install a working Lisp implementation and build the executable. Common Lisp is especially well suited to creating applications intended to be "forever" applications because Lisp doesn't (and is unlikely to) change. As long as implementations have maintainers updating them and adding new CPU architectures and OSes, you will have usable software.

However, for the sake of convenience, I will also make a web application that my father can link to his website so that anybody can try it out before downloading the native app. My father already has charts on his website providing the readings, so this will simply be a long-term upgrade to support his work.