כִּי־נֵ֙דֶר֙ נָדַ֣ר עַבְדְּךָ֔ בְּשִׁבְתִּ֥י בִגְשׁ֛וּר בַּאֲרָ֖ם לֵאמֹ֑ר אִם־ישיב [יָשׁ֨וֹב] יְשִׁיבֵ֤נִי יְהוָה֙ יְר֣וּשָׁלִַ֔ם וְעָבַדְתִּ֖י אֶת־יְהוָֽה׃
For thy servant vowed a vow while I abode at Geshur in Aram, saying: If the LORD shall indeed bring me back to Jerusalem, then I will serve the LORD.’
Read halakhic rulings (Jewish law) on II Samuel 15:8: and classical halakhic sources.