הֲל֤וֹא תֵֽדְעוּ֙ הֲל֣וֹא תִשְׁמָ֔עוּ הֲל֛וֹא הֻגַּ֥ד מֵרֹ֖אשׁ לָכֶ֑ם הֲלוֹא֙ הֲבִ֣ינֹתֶ֔ם מוֹסְד֖וֹת הָאָֽרֶץ׃
Know ye not? hear ye not? Hath it not been told you from the beginning? Have ye not understood the foundations of the earth?
Read halakhic rulings (Jewish law) on Isaiah 40:21: and classical halakhic sources.