Is lesbian (gay) by women allowed? Is it forbidden?
Lesbian sexual relations are forbidden, at the very least Rabbinically. [1] The discussion is in Yevamos 76a. This is also an explicit ruling in the Shulchan Aruch (Even Haezer 20:2) “women who play and hug each other [in sexual context] is forbidden as it is the act of the land of Mitzrayim that we are warned against, and it is fitting to give Rabbinical lashes over it since it is prohibited…”
The reference of “the acts of the land of Mitzrayim” refer to Vayikra 18:3 “Like the practice of the land of Mitzrayim [Egypt], in which you dwelled, you shall not do, and like the practice of the land of Canaan, to which I am bringing you, you shall not do, and you shall not follow their statutes.”
Therefore all forms of lesbianism is strictly prohibited. Nonetheless, a woman who performed such acts would not become forbidden to her husband nor be prohibited from marrying a Kohen. [2]
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[1] Otzar Haposkim in the name of the Tzafnas Paneach holds that this act is forbidden from the Torah. However the view of the Kiryas Melech Rav (brought in the Otzar Haposkim) is that the Biblical prohibition is only if the two women “marry” on a set basis however if their acts are only random then it is considered only promiscuous behavior which is only Rabbinically forbidden.
[2] Beis Shmuel (20:7).
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