לִבְּךָ֖ יֶהְגֶּ֣ה אֵימָ֑ה אַיֵּ֤ה סֹפֵר֙ אַיֵּ֣ה שֹׁקֵ֔ל אַיֵּ֖ה סֹפֵ֥ר אֶת־הַמִּגְדָּלִֽים׃
Thy heart shall muse on the terror: ‘Where is he that counted, where is he that weighed? Where is he that counted the towers?’
Read halakhic rulings (Jewish law) on Isaiah 33:18: and classical halakhic sources.