After a nazir completes his nezirut, he is obligated to visit the Temple and bring three sacrifices – a hatat (sin offering), an olah (an offering entirely burned on the altar) and a shelamim (an offering that is shared by the kohanim and the owner, aside from what is burned on the altar). In addition, the nazir is obligated to cut his hair.
Although the Torah clearly states that the nazir‘s hair be cut petah ohel mo’ed – “in the entrance to the Tabernacle” (see Bamidbar 6:18), our Gemara quotes a baraita that explains that doing so would be derekh bizayon – degrading. The requirement is therefore understood to be that the hair is cut in conjunction with the shelamim sacrifice, which is the only sacrifice that is said to be brought petah ohel mo’ed (see Vayikra 3:1-2). This also makes sense according to the flow of events, since the hair is burned under the pot in which the meat of the shelamim is cooked.
In the baraita, Rabbi Shimon Shezuri suggests that another halakha can be learned from the passage petah ohel mo’ed – one which obligates only a nazir, but not a female nezira. The explanation offered is that the sight of a woman with her hair uncovered was inappropriate in the Temple, so she should have her hair cut in the privacy of her home. In response to the objections that we find that a sota (a woman accused of adultery – see Bamidbar 5:18) has her hair uncovered in the Temple, Rabbi Shimon replied that the nezira comes kohelet u-pokeset – wearing makeup and rouge – while the sota does not.
The makeup described by the Gemara is kehal, כחל – more commonly known by its Persian name, kohl – which was prevalent in many ancient cultures across the world. Kohl’s black-blue color is derived from the mineral stibnite (Sb2S3), crystals of which are ground up and mixed with oil, fat or butter, then applied to the area around one’s eyes to emphasize them and make them appear larger. Stibnite is toxic and modern makeup has replaced the use of the substance, which is banned as a health risk in most developed countries.