וַיָּשֻׁ֖טוּ בְּכָל־הָאָ֑רֶץ וַיָּבֹ֜אוּ מִקְצֵ֨ה תִשְׁעָ֧ה חֳדָשִׁ֛ים וְעֶשְׂרִ֥ים י֖וֹם יְרוּשָׁלִָֽם׃
So when they had gone to and fro through all the land, they came to Jerusalem at the end of nine months and twenty days.
Read Kabbalistic (mystical) interpretations of II Samuel 24:8: Zohar and classical Jewish mystical sources, free online.