Tension exists in rabbinical literature concerning what constitutes proper and modest sex, and the will to have couples enjoy sex.

Rabbis recommend the missionary position–she below and he on top. However, Maimonides says, “A man may do whatever he wants with his wife. He may have intercourse with her at any time, and may kiss her on whatever limb of her body he wants. He may even engage in unnatural sex, as long as he does not spill seed in vain. It is a sign of piety not to show too much levity, but to sanctify himself at the time of intercourse.” (Mishne Torah, Hilkhot Issurei Biah 21:10)

Oral and anal sex are considered unnatural sex. Talmudic sources speak freely on this issue and, occasionally permit unnatural sex. “If it is occasional, and the desire of his heart is to come upon his wife in an unnatural way, it is permitted.” (Tosefot Yevamot 34b, Gold, 1992)