Mishnayos Sanhedrin Perek 2 Mishnah 2

The mishna continues, enumerating the halakhot pertaining to the king in similar matters: The king does not judge others as a member of a court and others do not judge him, he does not testify and others do not testify concerning him, he does not perform ḥalitza with his brother’s widow and his brother does not perform ḥalitza with his wife, and he does not consummate levirate marriage with his brother’s widow and his brother does not consummate levirate marriage with his wife, as all these actions are not fitting to the honor of his office. Rabbi Yehuda says: These are not restrictions, but his prerogative: If he desired to perform ḥalitza or to consummate levirate marriage, he is remembered for good, as this is to the benefit of his brother’s widow. The Sages said to him: They do not listen to him if he desires to do so, as this affects not only his own honor but that of the kingdom. And no one may marry a king’s widow, due to his honor. Rabbi Yehuda says: Another king may marry the widow of a king, as we found that King David married the widow of King Saul, as it is stated: “And I have given you the house of your master and the wives of your master in your bosom” (II Samuel 12:8).

הַמֶּלֶךְ לֹא דָן וְלֹא דָנִין אוֹתוֹ, לֹא מֵעִיד וְלֹא מְעִידִין אוֹתוֹ, לֹא חוֹלֵץ וְלֹא חוֹלְצִין לְאִשְׁתּוֹ. לֹא מְיַבֵּם וְלֹא מְיַבְּמִין לְאִשְׁתּוֹ. רַבִּי יְהוּדָה אוֹמֵר, אִם רָצָה לַחֲלֹץ אוֹ לְיַבֵּם, זָכוּר לָטוֹב. אָמְרוּ לוֹ, אֵין שׁוֹמְעִין לוֹ. וְאֵין נוֹשְׂאִין אַלְמָנָתוֹ. רַבִּי יְהוּדָה אוֹמֵר, נוֹשֵׂא הַמֶּלֶךְ אַלְמָנָתוֹ שֶׁל מֶלֶךְ, שֶׁכֵּן מָצִינוּ בְדָוִד שֶׁנָּשָׂא אַלְמָנָתוֹ שֶׁל שָׁאוּל, שֶׁנֶּאֱמַר (שמואל ב יב) וָאֶתְּנָה לְךָ אֶת בֵּית אֲדֹנֶיךָ וְאֶת נְשֵׁי אֲדֹנֶיךָ בְּחֵיקֶךָ: