A wool strip (לשון של צמר) col­ored red using the famed תולעת שני dye is a required ingre­di­ent for the Tahara process of he/she who’s skin nega has receded from it’s state of tumah.

What is שני תולעת?

Tosefta and tal­mud yerushalmi describe the תולעת שני as a worm, this is the approach adopted in a work spe­cific to this study1)1 who pin’s the שני תולעת as the red ker­mes dye pro­duced from the ker­mes insect found in the oak trees in north­ern Israel, a loca­tion some con­sider as hinted to by the tosefta (men­a­chot 9 6) which states that the שני from any­where but the moun­tains is invalid;

תכלת אין כשרה אלא מן החלזון שלא מן הילזון פסולה. שני התולעת מן התולע שבהרים הביא שלא מן התולעת שבהרים פסולה

The ram­bam,2)2 Medrash hagadol (מדה״ג שמות כה א) and rabbeinu bchaya define תולעת שני as being derived from red seeds sim­i­lar in size to the seeds of the חרוב that are sim­i­lar on color to sumac berries. rabbeinu bchaya writes the same (שמות כה ג), regard­ing the parah aduma and rea­sons that the col­or­ing can­not pos­si­bly be derived from an insect which is pro­hib­ited by the Torah for oral con­sump­tion.

The Torah some­times calls this color שני תולעת and some­times תולעת שני, in this instance, the wool strip is to be col­ored only from the red color derived from the תולעת (as other col­ors are derived as well)

The wool
A tongue of wool weigh­ing a shekel (apprx. 11.21 gram) is red-dyed using the שני תולעת dye

The water
A revi­ith of spring water


References   [ + ]

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