If you took a bus to synagogue on a rainy Shabbat or Yom Tov day, with umbrella in hand, would that be OK? There is no melachah involved because you are not driving. There is no amira le’nochri (asking a non‑Jew to perform a melachah on your behalf) involved because you are not asking the non‑Jew to drive for you. He is driving of his own accord for other non‑Jews. There is no violation of techum Shabbat (the prohibition not to travel on Shabbat or Yom Tov more than 2,000 amot beyond one’s residence), because the bus travels only in the city.
It is also difficult to find anything wrong with the umbrella. Presumably there is an eruv enclosure so there is no carrying violation involved. And according to the many authorities, including Rashi, who are of the opinion that building a provisional tent is permitted on Shabbat or Yom Tov, there is no melachah involved in opening the umbrella. Similarly, if you walk to your office in the city on Shabbat to assist a client in connection with an important transaction, taking care not to write or touch anything muktzah yourself, what would be wrong with that? There is no melachah involved in buying or selling on Shabbat.
But merely abstaining from the 39 melochot is not what Shabbat and Yom Tov is all about. Abstaining from the 39 melachot turns the weekday off, but it does not turn the Shabbat on.
Asks the Ramban, “What would the Shabbat be like had the Torah merely prohibited the 39 melachot? He responds, “A person could spend the entire Shabbat in physical labor. He could measure his grain and weigh his fruit, carry heavy furniture or barrels of wine from place to place. In a city enclosed with a valid eruv, it would be possible for many to go about business as usual. Markets and stores would be open and people would go Shabbat shopping. Laborers would get up early and hire themselves out for work. And Yom Tov would vanish into a regular weekday. The Torah refers to Yom Tov and Shabbat as Shabbaton, which means a day of rest, not a day of exertion.”
The liturgist in the Shabbat song “Ma Yeddidut” describes how the soul, once liberated from its weekday shackles, can soar on the wings of Shabbat, if we just let it. “Your steps should be leisurely; God made Shabbat for your pleasure, sleep is praiseworthy, it restores the spirit to the soul; my soul yearns to bask in Your affection.” And the prophet instructs us in the art of flying on Shabbat as follows, “If you refrain from running errands and pursuing your ambitions on My Holy Day, and if you designate the Shabbat a day of pleasure dedicated to My honor, then you will rejoice with Me and you will soar on high.”
And so anything that compromises the spirit of Shabbat and drags it down to weekday reality is prohibited, even if it is technically not a melachah. Certain activities by their very nature spoil the atmosphere of Shabbat, such as walking to work even if you do not write. Such activities are known as uvda dechol (weekday activities). Other activities, such as keeping the television on, demonstrate a disrespect for Shabbat. Yet other activities, such as carrying an umbrella on Shabbat, broadcast a workday atmosphere. Other activities simply confuse the onlooker and make him question your motive when you step off the bus on Shabbat.
Even permitted activities, such as bringing gifts to friends, must be done in a way that does not take on a commercial air. Thus, for example, three or more people should not arrive on Shabbat or Yom Tov lugging groceries, because it looks as if they are returning from the market. Rather, care should be taken to carry such items in a way that is different – derech shinui – from the way they are carried on a weekday.
An illustrative example of what might and what might not constitute uvda dechol is given by the Chatam Sofer. “Why” he asks, “is one permitted to travel by ship on Shabbat (boarded before Shabbat) but not by train?” Both are ten cubits off the ground and therefore the prohibition of techum Shabbat does not apply. The Chatam Sofer answers that in a ship you can celebrate the Shabbat in the comfort you would at home. In a train, however, you are always aware that you are traveling. The countryside races past the windows and you are constantly shaken up and focused on reaching your weekday destination. That is uvda dechol.