Talking to Alexa on Shabbos?

Ask the Rov: Why can’t I speak to my Alexa/Siri/Google Assistant on Shabbos if I’m not doing anything?

By Rabbi Chaim Hillel Raskin – Rov of Anash in Petach Tikvah

Halacha holds a person responsible for actions caused by his speech. For example, if one raises his voice and causes his animal to carry on Shabbos, he has transgressed an issur d’oraisa.¹ Likewise, if one scares an animal while threshing so it doesn’t eat, one transgresses on lo sachsom (muzzling it).²

Although the Gemara states that megadeif (cursing Hashem’s name) is the lone speech-only transgression for which one is liable, Rishonim explain that muzzling is worse since his speech results in an action.³

Based on this, poskim write that one may not activate a machine by voice if it will cause a melacha to happen.⁴ Rav Moshe Feinstein prohibits doing so even without the intention of causing the melacha if it will inevitably result (psik reishei).⁵

Halacha permits saying an incantation (lachash) on Shabbos to lock a snake or scorpion in place to prevent harm because it isn’t the normal way of trapping.⁶ However, activating a device through speech is normal today, and it could not be considered a shinui. Additionally, the activation is a direct effect and not a grama.

Besides the melachos that can result from the device’s activation —e.g., mav’ir for glowing heat or bulbs— there are Shabbos prohibitions inherent in the use of electricity itself (as with speaking into a microphone).

Smart devices are constantly recording ambient sound and listening for a “wake word,” such as ”Alexa.” Such devices should be turned off before Shabbos, but if you forgot, you may still speak near them, provided that you don’t speak to it.

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From The Weekly Farbrengen by Merkaz Anash