Exodus 3:5

5Then he said, “Do not come near; atake your sandals off your feet, for the place on which you are standing is holy ground.”

Exodus 19:22-23

22Also let the priests who come near to the Lord bconsecrate themselves, lest the Lord cbreak out against them.” 23And Moses said to the Lord, “The people cannot come up to Mount Sinai, for you yourself warned us, saying, d‘Set limits around the mountain and consecrate it.’”
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