the binding of the fringes, save for the obligation to include "a cord of blue" (Heb. ). The lack of detail on these points suggests that the tying of was to a great extent Oral Torah until the third to first century BCE with the codifying of the Talmud. The primary mnemonic purposes of this are expressed clearly: wearing reminds a daily practitioner to bring God's love into action by practicing all other . The paragraph from Numbers is included in daily prayer as the final paragraph of the Shema. Here, also remind Jews that they are no longer slaves. Rabbinic Judaism The Talmud equates observance of with that of all the mitzvot. Maimonides includes it as a major commandment along with circumcision and the Passover offering. The tallit and tallit katan are four-cornered garments worn by practicing Jews which incorporate . The garment itself is commonly referred to as .The tallit is typically worn over the shirt/ clothes, like a cloak, whereas the tallit katan (or arba kanfot) is smaller and worn underneath the clothing. It is a simplistic garment with a front and back fold, creating four corners to which the tzitzit are fastened. The blue thread mentioned in the Torah, tekhelet, is omitted by most Rabbinic Jews due to controversy over the dye-making process. Fabrics The medieval rabbis debated the source of the obligation for garments made from different types of fabric. All agree that garments made from wool or linen (the typical materials of Biblical garments) require by Biblical law. However, they debated whether the requirement is Biblical or rabbinic if the garment is made from any other material. The Shulchan Aruch ruled that this obligation is rabbinic, while the Rema ruled that it is Biblical. The Torah forbids shatnez ("intertying" wool and linen together). However, unlike other forms of kil'ayim (combinations of various phenomena like planting different types of seed or ploughing with different animals), there is an exception to the rule: was not only allowed but required in the priestly garments, which combined dyed-wool and linen threads. According to the rabbis, this exemption to applied only while performing priestly service. Rabbinic Judaism (but not Karaite Judaism or Samaritanism) makes a further exemption to this law for , based on the Torah's juxtaposition of the laws for and in Deuteronomy 22:11-12. Thus, according to rabbinic Judaism, both laymen and priests were supposed to wear mixtures