“Three things are a glimpse of the world to come: שַׁבָּת שֶׁמֶשׁ וְתַשְׁמִישׁ (Shabbat shemesh ve-tashmish), Sabbath, sun, and ‘service‘” (BT Berakhot 57b).
“Rabbi Ḥizqiyah said in the name of Rav: Man will one day give reckoning for everything his eye saw which, although permissible, he did not enjoy” (JT Qiddushin 4:12, 66d).
“Rav Kahana entered and lay down beneath the bed of Rav [Abba]. He heard that he was talking and laughing and having sexual intercourse. He said, ‘The mouth of Abba appears as if he never tasted this dish.’ He said to him, ‘Qahana, get out; this is not proper behavior!’ He said to him, ‘It is Torah, and I must learn it” (BT Ḥagigah 5b).
“Shekhinah abides neither through gloom nor laziness nor frivolity nor levity nor talk nor idle chatter [or: vain pursuits], but only through the joy of mitsvah” (BT Shabbat 30b, cf. Zohar 1:50a).
“Rabbi Yoḥanan son of Dahavai said: The ministering angels told me four things: People are born lame because they overturned their table; dumb, because they kiss ‘that place;’ deaf, because they converse during cohabitation; blind, because they look at ‘that place.’ But this contradicts the following: Imma Shalom [wife of Rabbi Eli’ezer son of Hyrkanos, and sister to Rabban Gamaliel of Yavneh] was asked: Why are your children so exceedingly beautiful? She replied: [Because my husband] ‘converses’ with me neither at the beginning nor at the end of the night, but at midnight; and when he ‘converses,’ he uncovers a hand breadth and covers a hand breadth, and is as though he were compelled by a שֵׁד (shed), demon [alt., שָׁד (shad), breast]. And when I asked him, What is the reason for this, he replied, ‘So that I may not think of another woman, lest my children be as bastards’—there is no difficulty: this refers to conjugal matters; the other refers to other matters.
Rabbi Yoḥanan said: The above is the view of Rabbi Yoḥanan son of Dehavai; but our Sages said: The Halakhah is not as Rabbi Yoḥanan son of Dehavai, but a man may do whatever he pleases with his wife [with her consent]: A parable; Meat which comes from the butcher, may be eaten salted, roasted, cooked or boiled; so with fish from the fishmonger. Amemar said: Who are the ‘ministering angels?’ The Rabbis. For should you maintain it literally, why did Rabbi Yoḥanan say that the Halakhah is not as Rabbi Yoḥanan son of Dehavai, seeing that the angels know more about the formation of the fetus than we? And why are they designated ‘ministering angels?’—because they are as distinguished as they.
A woman once came before Rabbi and said, ‘Rabbi! I set a table before my husband, but he overturned it.’ Rabbi replied: ‘My daughter! Torah has permitted you to him—what then can I do for you?’ A woman once came before Rav and complained. ‘Rabbi! I set a table before my husband, but he overturned it.’ Rav replied; Wherein does it differ from a fish?
And you shall not stray after your own heart (Numbers 15:39). [Deducing] from this Rabbi taught: One may not drink out of one goblet and think of another. Ravina said: This is necessary only when both are his wives” (BT Nedarim 20a–b).