The siyag or fence around the law requires practices that keep us far from violations. For example since writing on Shabbat is forbidden according to Jewish tradition, observant Jews do not touch writing implements such as pencils and pens on Shabbat. Avoiding those objects is not only about avoiding temptation; it is also about keeping away from the objects that will remind us about our workaday concerns. Shabbat is an entirely different experience for those who put away their cellphones, computers, and other electronic devices for Shabbat, saving the time for direct personal interaction and restful activity. The fence demarcates a holy space.
(commentary originally appears in Text Me: Ancient Jewish Wisdom Meets Contemporary Technology)