The Jewish Talmud is a treasure trove of legalism. There are rules for everything, especially about keeping the Sabbath. There’s even a section on what kinds of knots one can tie on the Sabbath. Here’s a section discussing if it’s okay for a woman to tie the bands of her hood,
…The case is, that the bands of the hood are always tied, and the woman slips on the hood without untying or tying the bands, and we might assume that for this reason the knot is considered permanent; he therefore informs us, that if a hair become entangled in the hood, the woman may tie and untie the bands.
So in other words, the woman should try to keep her bands permanently tied on the Sabbath to avoid any opportunity to slip, and she can only tie or untie her hood if her hair becomes entangled. If she ties her hood bands in any other scenario, she could be in danger of working on the Sabbath, thus breaking it. And there are plenty more rules for other knots too–for example when one should tie bands on leather flasks, or a pot of meat, or a girdle, or the straps of one’s sandals. The Jews believed that following all these rules helped them avoid breaking the Sabbath. And there are many many many other Sabbath rules about hunting, weaving, handling utensils, and even clearing crumbs off the table (yes, there are rules on that). The Jews were serious about these rules, but Jesus demolished them with the teachings of the purpose and full meaning of the law, and how the law addressed the desires of the heart. That’s one reason why His ministry was so radical at the time and still is today to modern-day Jews. These extra rules were not the law of God. They missed the point.