Rabbi Kahana once went and hid under Rav's bed to see how his teacher conducted himself when he had intercourse with his wife. He noted that Rav chatted and joked with her before having sex.
Rabbi Kahana said: "It's as if he's never tasted such good food before!"
"Kahana, are you in here?" said Rav. "Get out, it's not good manners."
Rabbi Kahana said: "It is Torah and I have to learn."

Perhaps tongue-in-cheek, but Kahana, adopting Akiva's refrain from a previous generation, defends himself from reproof by pointing out that his voyeurism is in fact motivated by his desire to understand God's teaching. And his teacher's sexuality is just as much a part of what Rav has to teach as any words of wisdom he might utter. The body's activity becomes the site of knowlegde. And sex is seen as a form of religious activity, a spiritual resource.

Howard Cooper, The Alphabet of Paradise