Exodus 19:12-13

12Put limits for the people around the mountain and tell them, ‘Be careful that you do not approach the mountain or touch the foot of it. Whoever touches the mountain is to be put to death.

13They are to be stoned or shot with arrows; not a hand is to be laid on them. No person or animal shall be permitted to live.’ Only when the ram’s horn sounds a long blast may they approach the mountain.”