וַיָּבֹ֤א יוֹאָב֙ אֶל־הַמֶּ֔לֶךְ וַיֹּ֖אמֶר מֶ֣ה עָשִׂ֑יתָה הִנֵּה־בָ֤א אַבְנֵר֙ אֵלֶ֔יךָ לָמָּה־זֶּ֥ה שִׁלַּחְתּ֖וֹ וַיֵּ֥לֶךְ הָלֽוֹךְ׃
Then Joab came to the king, and said: ‘What hast thou done? behold, Abner came unto thee; why is it that thou hast sent him away, and he is quite gone?
Read halakhic rulings (Jewish law) on II Samuel 3:24: and classical halakhic sources.