וַיַּ֧עַן אִתַּ֛י אֶת־הַמֶּ֖לֶךְ וַיֹּאמַ֑ר חַי־יְהוָ֗ה וְחֵי֙ אֲדֹנִ֣י הַמֶּ֔לֶךְ כִּ֠י אִם־בִּמְק֞וֹם אֲשֶׁ֥ר יִֽהְיֶה־שָּׁ֣ם ׀ אֲדֹנִ֣י הַמֶּ֗לֶךְ אִם־לְמָ֙וֶת֙ אִם־לְחַיִּ֔ים כִּי־שָׁ֖ם יִהְיֶ֥ה עַבְדֶּֽךָ׃
And Ittai answered the king, and said: ‘As the LORD liveth, and as my lord the king liveth, surely in what place my lord the king shall be, whether for death or for life, even there also will thy servant be.’
Find Mishnaic references to II Samuel 15:21: , passages from the 63 tractates of the Mishnah.