Exodus 20:25

Altar of stone. In cases where, notwithstanding the divine preference of the previous verse, the people would erect a more permanent and honorable altar of stone, God required that the stones be left in their rough, natural state.

Lift up thy tool. Here again in His ardent desire, prompted by love, that His people should not be corrupted by idolatry, God forbids the elaborate carving of the altars with objects that might woo them to idolatry. There is suggested the further thought that if we presume to put something of our own into the sacrifice as a ground for acceptance, we render it in vain. Self-obtrusion, however well intended, is pollution. The altar is an expression of God’s will. Try to improve it, and it becomes instead an expression of the will of the would-be improver. The altar of self is not the altar of God. Sacrifices offered upon it may satisfy the worshiper; they cannot be pleasing to God. Let us not lose the lesson found in the experience of Cain (Gen. 4:3, 4). The pillar of Simeon Stylites did not raise the value of his prayers. Our prayers would have a better chance of reaching heaven if they came from a contrite heart at the foot of the pillar (see Isa. 66:1, 2).