לֹא־יוּכַ֣ל בַּעְלָ֣הּ הָרִאשׁ֣וֹן אֲשֶֽׁר־שִׁ֠לְּחָהּ לָשׁ֨וּב לְקַחְתָּ֜הּ לִהְי֧וֹת ל֣וֹ לְאִשָּׁ֗ה אַחֲרֵי֙ אֲשֶׁ֣ר הֻטַּמָּ֔אָה כִּֽי־תוֹעֵבָ֥ה הִ֖וא לִפְנֵ֣י יְהוָ֑ה וְלֹ֤א תַחֲטִיא֙ אֶת־הָאָ֔רֶץ אֲשֶׁר֙ יְהוָ֣ה אֱלֹהֶ֔יךָ נֹתֵ֥ן לְךָ֖ נַחֲלָֽה׃ (ס)
maka suaminya yang pertama, yang telah menyuruhnya pergi, tidak boleh mengambilnya kembali menjadi istrinya setelah perempuan itu dinajiskan, sebab hal itu adalah kekejian di hadapan Yang Mahakekal. Janganlah engkau mendatangkan dosa atas negeri yang diberikan Yang Mahakekal, Allahmu, kepadamu sebagai milik pusaka.
Mishneh Torah, Marriage
Intercourse prohibitions according to the Torah for which there is no punishment of karet are called “negative prohibitions”. They are also called “holy prohibitions”. There are nine [such prohibitions] and they are: a widow to a high priest, a divorced woman or zona or ḥalala to a high priest or to an ordinary priest, a mamzeret to an Israelite man, an Israelite woman to a mamzer, an Israelite woman to an Ammonite or Moabite man, an Israelite woman to one with crushed [genitals], or severed [genitals], one’s ex-wife after she has remarried, one’s yevama who married a stranger while still under the yavam’s control. A ḥalutza is like a divorced woman and is forbidden to a priest according to Rabbinic law. The Gibeonites are like mamzerim, whether male or female, and they are prohibited according to Rabbinic law. The Gibeonites will be explained in the Laws of Forbidden Intercourse.
Mishneh Torah, Forbidden Intercourse
2. When a mamzer marries a Jewish women or a Jewish man marries a female mamzer, once they enter into relations after consecration, they are punished by lashes. If the man consecrates the woman, but does not enter into relations, he does not receive lashes. If they enter into relations without consecration, they do not receive lashes because of relations with a mamzer. For the only instance where relations that involve a negative prohibition incur the punishment of lashes without the woman being consecrated is relations between a High Priest and a widow, as will be explained. When a man remarries his divorcee after she married another person, the offspring are acceptable. For she is not considered an ervah.
Shulchan Arukh, Even HaEzer
If a rumor spread that she was married to s0-and-so, and another man came forth and betrothed her in front of court, we examine the circumstances of the rumored betrothal. If definite eyewitnesses testified that she is betrothed to the first man, the second betrothal is null. If not, the first man whose betrothal was imputed by rumor grants her divorce, and the second man marries her, since his betrothal was definite. If the second man divorced her, the first man may not marry her lest people will say that he remarried his ex-wife from betrothal after she had subsequently betrothed another (which is forbidden explicitly in Deuteronomy 24:4). If the second man brought her under the chupa (i.e. completed the marriage) before she was divorced from the first man, she is forever forbidden to him (the second man), even after divorce from the first man (See supra chapter 31 se'if 4).