Deuteronomy 4:15-18

15Remember when the Lord spoke to you at Mount Horeb from the middle of the fire. You did not see him in any shape. So be very careful about everything that you do.

16Do not make any image to be your god. That would be a sin. Do not make an image in any shape as your idol. Do not copy the shape of a man or a woman,

17or the shape of any animal or bird.

18Do not copy the shape of anything that moves along the ground, or any fish that swims in the deep water.