Exodus 19:10-12

American Standard Version

¹⁰ And Jehovah said unto Moses, Go unto the people, and sanctify them to-day and to-morrow, and let them wash their garments, ¹¹ and be ready against the third day; for the third day Jehovah will come down in the sight of all the people upon mount Sinai. ¹² And thou shalt set bounds unto the people round about, saying, Take heed to yourselves, that ye go not up into the mount, or touch the border of it: whosoever toucheth the mount shall be surely put to death: