A man must not remarry his ex-wife after she has married someone else

then her former husband who sent her away is not allowed to take her again to be his wife, since she has been defiled; for that is an abomination before the LORD, and you shall not bring sin on the land which the LORD your God gives you as an inheritance.

Hebrew

ד לֹא-יוּכַל בַּעְלָהּ הָרִאשׁוֹן אֲשֶׁר-שִׁלְּחָהּ לָשׁוּב לְקַחְתָּהּ לִהְיוֹת לוֹ לְאִשָּׁה, אַחֲרֵי אֲשֶׁר הֻטַּמָּאָה--כִּי-תוֹעֵבָה הִוא, לִפְנֵי יְהוָה; וְלֹא תַחֲטִיא, אֶת-הָאָרֶץ, אֲשֶׁר יְהוָה אֱלֹהֶיךָ, נֹתֵן לְךָ נַחֲלָה. {ס}

Greek

4 οὐ δυνήσεται ὁ ἀνὴρ ὁ πρότερος ὁ ἐξαποστείλας αὐτὴν ἐπαναστρέψας λαβεῖν αὐτὴν ἑαυτῷ γυναῖκα μετὰ τὸ μιανθῆναι αὐτήν, ὅτι βδέλυγμά ἐστιν ἐναντίον κυρίου τοῦ θεοῦ σου· καὶ οὐ μιανεῖτε τὴν γῆν, ἣν κύριος ὁ θεὸς ὑμῶν δίδωσιν ὑμῖν ἐν κλήρῳ.

• Parashah: Ki Tetze
• Mishneh Torah: Women — Divorce

• Deuteronomy 24:4

Enumeration and classification from BibleData. The Greek is the Septuagint reading of the same verse, carried by the source for comparison.