May a woman apply makeup to her face on Shabbat?
Although one might argue that makeup should be permissible in the interest of Kevod Shabbat (showing honor to Shabbat), a person cannot show honor to Shabbat by doing something that constitutes a violation of Shabbat. Applying makeup to one's face violates the Shabbat prohibition of Tzovei'a, dyeing, and is thus forbidden. Although the prohibition of dyeing does not apply to coloring one's face on the level of Torah law, nevertheless, the Sages enacted a prohibition against any kind of dyeing on Shabbat, including applying makeup to one's face. Applying lipstick entails also the separate prohibition of "Memahek," changing the form of a solid substance into a liquid-type substance.
Therefore, women must be instructed to apply makeup only before Shabbat, and not on Shabbat itself. (Menuhat Ahava, Helek 3, Perek 13, Halachot 6-7)
Today there are special types of makeup produced in such a way that circumvents these prohibitions of Tzovei'a and Memahek, and they come with a symbol of Rabbinical supervision. A number of leading Rabbis allow using such makeup on Shabbat, and thus women who so desire may apply these brands of makeup on Shabbat. Other brands, however, should be applied only before Shabbat, and not on Shabbat itself.
