וְהָיָה֙ בַּיּ֣וֹם הַה֔וּא וְנִשְׁכַּ֤חַת צֹר֙ שִׁבְעִ֣ים שָׁנָ֔ה כִּימֵ֖י מֶ֣לֶךְ אֶחָ֑ד מִקֵּ֞ץ שִׁבְעִ֤ים שָׁנָה֙ יִהְיֶ֣ה לְצֹ֔ר כְּשִׁירַ֖ת הַזּוֹנָֽה׃
And it shall come to pass in that day, that Tyre shall be forgotten seventy years, according to the days of one king; after the end of seventy years it shall fare with Tyre as in the song of the harlot:
Read halakhic rulings (Jewish law) on Isaiah 23:15: and classical halakhic sources.