Clothing serves as a basic human necessity, but it can also be elevated into a profound spiritual symbol. While the preceding instruction restricts a person's wardrobe by forbidding the prohibited mixture of wool and linen, the requirement to attach fringes to one's garments transforms everyday attire into a positive emblem. This addition serves as a constant reminder of a person's ultimate purpose and their duty to God [רש״ר הירש]. These fringes are formed by twisting and braiding strands of thread together, resembling a chain [אבן עזרא, רשב״ם, חזקוני]. Specifically, this refers to the upper section of the fringe closest to the fabric, where a single thread wraps tightly around the others to create a bound appearance [הכתב והקבלה]. Conceptually, this tightly bound section represents the submission of humanity and the necessary restraint of personal desires in deference to the will of God [רש״ר הירש].
The immediate placement of this instruction right after the prohibition against mixing wool and linen is highly deliberate. It introduces a fundamental legal principle: a positive commandment overrides a negative one. Consequently, the Torah permits the blending of wool and linen exclusively for the purpose of fulfilling the commandment of the fringes. While an ordinary mixture of these fabrics remains strictly forbidden, combining them for this specific ritual creates a permitted and holy connection [אלשיך]. However, this allowance is strictly limited to the necessary performance of the commandment. A person may not wear multiple fringed garments simultaneously if it results in an unnecessary mixture of wool and linen, as a single garment is entirely sufficient to fulfill the obligation [רלב״ג].
The obligation to attach these fringes rests squarely on the individual wearing the clothing, rather than on the garment itself as an independent object [ביאור יש״ר]. Furthermore, the fringes must be actively created on a garment that is already complete. They cannot be attached to an unfinished piece of clothing. For instance, if someone attaches fringes to a garment with only three corners and subsequently adds a fourth corner, the original fringes are rendered invalid [תורה תמימה, מלבי״ם]. Similarly, a person is forbidden from wearing a garment that requires fringes if they are unable to properly tie the threads to it beforehand [העמק דבר].
The fringes must be tied precisely at the outermost edges of the garment, rather than anywhere in the middle [תורה תמימה, רלב״ג]. The specification of four corners naturally exempts any garment possessing only three. The primary approach among commentators, however, is that garments with five or more corners remain obligated, as the requisite four corners are already present within them. The type of clothing subject to this rule is specifically daytime attire designed to protect the body from cold, heat, or insects, which exempts nightwear and bed linens [הכתב והקבלה, תורה תמימה]. The clothing must also belong to the wearer; borrowed garments are exempt from this requirement, at least for the first thirty days of use [תורה תמימה].
To qualify for this obligation, the clothing must be substantial enough to cover at least a small person. This excludes small scarves that fail to cover the majority of the head and body [רלב״ג, תורה תמימה, ביאור יש״ר]. Conversely, this broad definition of a covering ensures that a blind person is fully obligated to wear the fringes. Even though the commandment elsewhere mentions that one must look upon the fringes, a blind person is still required to participate because their garment functions as a proper covering [קיצור בעל הטורים, תורה תמימה]. Finally, the immediate proximity of this instruction to the subsequent laws concerning marriage serves as the traditional basis for the widespread custom of spreading a prayer shawl over a bride and groom during their wedding ceremony [הדר זקנים].