Know that the act of union is a holy and pure matter when carried out in the proper manner, at the proper time, and with the proper intentions. A person should not think there is anything degrading and unbecoming to the act of union.
“You shall sanctify yourselves and you shall be holy (Lev. 11:44). This teaches that one should sanctify oneself during intercourse. What is the relevance of sanctification here? Rabbi Judah ben Jacob said: It means that one should not act licentiously or obscenely, or with whorish intentions like animals, for this is how animals act.
The Gemara cites another halakha (law) derived from the verse mentioned in the previous discussion. Rami bar Ḥama said that Rav Asi said: It is prohibited for a man to force his wife in the conjugal mitzva, i.e., sexual relations, as it is stated: “And he who hastens with his feet sins” (Proverbs 19:2). The term his feet is understood here as a euphemism for intercourse.
§ Rav Yehuda says that Rav says: There was an incident involving a certain man who set his eyes upon a certain woman and passion rose in his heart, to the point that he became deathly ill. And they came and asked doctors what was to be done with him. And the doctors said: He will have no cure until she engages in sexual intercourse with him. The Sages said: Let him die, and she may not engage in sexual intercourse with him. The doctors said: She should at least stand naked before him. The Sages said: Let him die, and she may not stand naked before him. The doctors suggested: The woman should at least converse with him behind a fence in a secluded area, so that he should derive a small amount of pleasure from the encounter. The Sages insisted: Let him die, and she may not converse with him behind a fence.
(יב) וְכֵן אָסְרוּ חֲכָמִים שֶׁלֹּא יְשַׁמֵּשׁ אָדָם מִטָּתוֹ וְלִבּוֹ מְחַשֵּׁב בְּאִשָּׁה אַחֶרֶת. וְלֹא יִבְעל מִתּוֹךְ שִׁכְרוּת וְלֹא מִתּוֹךְ מְרִיבָה וְלֹא מִתּוֹךְ שִׂנְאָה וְלֹא יָבוֹא עָלֶיהָ עַל כָּרְחָהּ וְהִיא יְרֵאָה מִמֶּנּוּ. וְלֹא כְּשֶׁיִּהְיֶה אֶחָד מֵהֶן מְנֻדֶּה. וְלֹא יָבוֹא עָלֶיהָ אַחַר שֶׁגָּמַר בְּלִבּוֹ לְגָרְשָׁהּ. וְאִם עָשָׂה כֵּן הַבָּנִים אֵינָן הֲגוּנִים אֶלָּא מֵהֶן עַזֵּי פָּנִים וּמֵהֶן מוֹרְדִים וּפוֹשְׁעִים:
(12) Similarly, the sages forbade a man to have marital relations while thinking of another woman. Nor may he initiate sex while drunk, nor out of spite or hatred, nor may he rape her or initiate sex while she is afraid. Nor may they have sex while either of them are excommunicated nor after he has decided to divorce her. If [the husband] does any of those things, the children will not be proper [citizens] but brazen, rebellious [people] and criminals.
13.One should not have intercourse with his wife unless she has a desire for it, but not otherwise, and certainly one is forbidden to force her. Nor should one have intercourse with his wife if he hates her, or if she hates him, and she tells him that she does not want his attention, although she does consent to having cohabitation. If he has determined to divorce her, and she is not aware of it, he is not allowed to cohabit with her even though he does not hate her. Nor should one be with his wife when she is actually asleep, nor while he or she is intoxicated.
[There is] for the Jew an ideal of sexuality. While we know well that most human sexuality hardly approaches this exalted pictures, it does provide us with a point of view. It indicates strongly that we Jews should stand opposed to the current moves toward the "the demystificication" of sexuality, which seeks to define coupling as purely biological function. We are made most fully human by the fact that this act, shared by us with the animal kingdom, can be raised in our consciousness to the rung of the raza de-yihuda - the sublime mystery of union, Sexuality at its fullest is brimming with religious kavanah [intention]: this is a teaching we would be fools to ignore. If we cannot fulfill the ideal, we can begin to approach it.