“Then Moses turned and went down from the mountain with the two tablets of the testimony in his hand, tablets which were written on both sides; they were written on one side and the other.”

Exodus 32:15

Appreciation of God’s covenant cannot come without a page-turning.  The two-sided writing indicates that a change is necessary for anyone to be found in compliance with God’s will.

“For when the priesthood is changed, of necessity there takes place a change of law also.”

Hebrews 7:12, New American Standard Bible