“Let there be light” might be an important part of the Old Testament, but for Orthodox Jews, it can be a burden on the Sabbath.

The traditional day of rest, which starts at sundown on Friday and ends at sundown on Saturday, forbids any work, including turning on lights, ovens, blenders, whathaveyou. That’s why dozens of major appliance brands like KitchenAid, GE, LG, and Whirlpool consult with Jonah Ottensoser at kosher-certification company Star-K to offer appliances with something called “Sabbath Mode.”

The Sabbath Mode

The short version? The Sabbath mode keeps lights off in your refrigerator, automatically ends timers, and so on, so Orthodox Jews don’t have to interact with their appliances.

The long version? Well, in 1997 Whirlpool reached out to Star-K to help the company make Sabbath-compliant ovens. Whirlpool actually patented its Sabbath Mode in 1988, and over time other companies have followed suit, developing software and even special models specifically for this small subset of people (Ottensoser estimates about 100,000 families in the United States).

Here are a few of the specifications:

Ovens

Regular ovens shut off automatically after 12 hours; Sabbath-compliant ones keep on heating, so people can cook throughout the day. According to Star-K, “no lights, digits, solenoids, fans, icons, tones or displays will be activated/modified in the normal operation of the oven.” There’s even a built-in delay “between the request for temperature change and its actual implementation,” so you can’t ever be accused of working to change the temperature. Many also have a “timed bake” option, where the timer shuts off after a certain time rather than requiring you to turn it off.

Refrigerators

Lights, digits, icons, tones, alarms, and fans won’t be activated or deactivated when you open or close a refrigerator door in Sabbath mode. Ice and coldwater systems are also turned off, “since they invariably use electrical solenoids and motors to operate.”

A former engineer, Ottensoser works closely with major companies on these alterations, and he has thousands of Orthodox testers double-checking his work.

Why Companies Play Along

These models aren’t only sold to the Orthodox Jewish community; you can find them at Jewish-focused stores in Brooklyn as well as Sears in Iowa. “That’s the beauty,” said Ottensoser. “They program it into their model universally.”

Yet clearly these companies are spending a significant amount of time and energy pleasing a small group of consumers. Foodtech expert Brian Frank says there’s a reason for that: Appliance companies “want to build products that don’t exclude people, because that means they exclude a market opportunity or some innovation.”

He sees Sabbath Mode as a perfect example of the power of the connected kitchen. One piece of hardware can be programmed a variety of different ways to appeal to different groups of people. In the future, you’ll be able to upgrade your software or even download certain programs in order to expand and change the capabilities on your oven or refrigerator (like we all do with our smartphones, tablets, and computers). So instead of buying oven model GBS309P from Whirlpool as your only Sabbath-Mode option, you’d simply be able to download an app for timed bake, for example.

Frank believes we’ll even have commercial and consumer software options, where the same oven or microwave or refrigerator hardware is used in both environments, simply with different software, thus closing up a longstanding divide in the kitchen world.

In other words, this kind of technology gives “let there be light” a whole different meaning.