Parsha Mitzvot: Yitro: Mitzvah 33 – Concept 88
“Six days a week shall you work and accomplish all your work, but the seventh day is Shabbat to God, your Lord, you shall not do any work, you, your son, your daughter, your slave, your maidservant, your animal, and your convert within your gates.” (Exodus 20:9-10) We may not perform prohibited labor on the Shabbat. (Rambam, Hilchot Shabbat)
The 21st of Shevat is the Yahrtzeit of Rav Yitzchak of Nezchizh (1868), who explains that we are prohibited from physical labor, but not from spiritual work that is the highest form a emulation of God. We cannot be distracted from this most important and challenging work. Shabbat is our opportunity to exclusively focus on our spiritual development and growth. (Rishpei Aish)