Melacha

Halakha (Jewish law), especially the Talmud tractate Shabbat, identifies thirty-nine categories of activity prohibited on Shabbat (Hebrew: ל״ט אבות מלאכות‎, lamed tet avot melakhot), and clarifies many questions surrounding the application of the biblical prohibitions. Many of these activities are also prohibited on the Jewish holidays listed in the Torah, although there are significant exceptions permitting carrying and preparing food under specific circumstances.

There are often disagreements between Orthodox Jews and Conservative Jews or other non-Orthodox Jews as to the practical observance of the Sabbath. It is of note that the (strict) observance of the Sabbath is often seen as a benchmark for orthodoxy and indeed has legal bearing on the way a Jew is seen by an orthodox religious court regarding their affiliation to Judaism.

The commandment to keep Shabbat as a day of rest is repeated many times in the Tanakh, the Hebrew Bible. Its importance is also stressed in Exodus 31:12-17:

And the LORD spoke unto Moses, saying: 'Verily ye shall keep My sabbaths, for it is a sign between Me and you throughout your generations, that ye may know that I am the LORD who sanctify you. Ye shall keep the sabbath therefore, for it is holy unto you; every one that profaneth it shall surely be put to death; for whosoever doeth any work (melakha—מְלָאכָה) therein, that soul shall be cut off from among his people. Six days shall work be done; but on the seventh day is a sabbath of solemn rest, holy to the LORD; whosoever doeth any work in the sabbath day, he shall surely be put to death. Wherefore the children of Israel shall keep the sabbath, to observe the sabbath throughout their generations, for a perpetual covenant. It is a sign between Me and the children of Israel for ever; for in six days the LORD made heaven and earth, and on the seventh day He ceased from work and rested.'

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