It is no secret that we love the culture of open-source software. There is so much to celebrate in what it cultivates for the broader tech community: knowledge sharing, skill-building, collaboration just to name a few. Yet, is there ever a time to keep some knowledge behind locked doors? Is knowledge always meant to be free?

This is a challenging question. The idea that sometimes it is better to keep knowledge protected feels foreign and contrary to so many of the values that we aspire to in open-source culture. However, the Talmud itself offers a fascinating window into this question through the lens of this week's parsha of Teruma.

The parsha details many of the instruments and the parameters of the Mishkan, the Tabernacle, that accompanied the people through the desert, and would serve later as the paradigm for the Temple in Jerusalem. Among the items described is the lechem hapanim -- the showbread. This bread (or perhaps matzo) was kept out inside the Tabernacle all week, and consumed by the Kohanim at the end of the week. The recipe for this showbread was incredibly exacting and precise, and it was also closely guarded.

Indeed, only one family knew this recipe. The House of Garmu passed on from generation to generation the formula, or code, for this showbread, and they did not share it with anyone else. There were other families that did similarly for other elements of the Tabernacle. The Mishnah declares that some of these families, like the Garmu family, are to be praised for their closed-source, and others are to be condemned. What is the difference between those who are praised and those who are condemned?

The Talmud clarifies the reason.

The Garmu family understood that at one point in the future there would be no more Temple. It would be destroyed, and with it, all the vessels and instruments of the Temple would also be destroyed. If they shared this recipe for this most special bread that had such a lofty place in the Temple wide and far, then at one point in the future, it would be used for purposes in direct contradiction to everything the Temple once stood for. It was for that reason they closely guarded it for generations.

Those other families who also guarded and closed the "source code" for their particular elements of the Temple who were not looked upon favorably by the Sages did not have the same admirable motivations.

What does this all say about our world of software and open-source technology? Is there ever a time when it makes sense to keep something behind a process to enter, or should everything have a wide-open door? At the very least, the question itself is worth considering over this Shabbat.

Shabbat Shalom,

Yechiel && Ben