The types of speech included in the prohibition of mundane speech are prohibited not because they indirectly cause the performance of prohibited acts on Shabbat, but because the very act of speaking about mundane matters impinges upon the sanctity of Shabbat; as such talk does not suit the holy atmosphere of Shabbat, it is appropriate to avoid meaningless chatter as well.

Any conversation about commerce and business is prohibited on Shabbat. It is also prohibited to talk about plans for future transactions, for example to say, “I will buy a new car soon.” Nevertheless, it is permitted to think about business on Shabbat. Even so, it is advisable to avoid thinking about such matters as well, in order to enjoy true mental rest, which can be achieved only by total detachment from all mundane matters.

Not only is discussion of business matters prohibited on Shabbat, but one may also not talk about other prohibited labors, for example, to say, “On Tuesday, people will be coming to paint the house.” Furthermore, during Shabbat one may not ask a person to perform work after Shabbat that is prohibited on Shabbat. For example, one may not arrange with a taxi driver to take him somewhere after the conclusion of Shabbat.

Although one may not say on Shabbat, “I am going to sleep so that I will have the strength to work after Shabbat,” in practice one may sleep for that same purpose, as the act of sleeping itself does not indicate one’s intention.