A childless widow must not remarry until the ties with her brother-in-law are removed

"When brothers live together and one of them dies and has no son, the wife of the deceased shall not be married outside the family to a strange man. Her husband's brother shall go in to her and take her to himself as wife and perform the duty of a husband's brother to her.

Hebrew

כִּי־יֵשְׁבוּ אַחִים יַחְדָּו וּמֵת אַחַד מֵהֶם וּבֵן אֵין־לוֹ לֹא־תִהְיֶה אֵשֶׁת־הַמֵּת הַחוּצָה לְאִישׁ זָר יְבָמָהּ יָבֹא עָלֶיהָ וּלְקָחָהּ לוֹ לְאִשָּׁה וְיִבְּמָהּ׃ ‬

Greek

ἐὰν δὲ κατοικῶσιν ἀδελφοὶ ἐπὶ τὸ αὐτὸ καὶ ἀποθάνῃ εἷς ἐξ αὐτῶν σπέρμα δὲ μὴ ᾖ αὐτῷ οὐκ ἔσται ἡ γυνὴ τοῦ τεθνηκότος ἔξω ἀνδρὶ μὴ ἐγγίζοντι ὁ ἀδελφὸς τοῦ ἀνδρὸς αὐτῆς εἰσελεύσεται πρὸς αὐτὴν καὶ λήμψεται αὐτὴν ἑαυτῷ γυναῖκα καὶ συνοικήσει αὐτῇ

• Parashah: Ki Tetze
• Mishneh Torah: Women — Levirate Marriage and Release

• Deuteronomy 25:5

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