15 You saw no form on the day God spoke to you at Horeb from out of the fire. Remember that. Carefully guard yourselves 16 so that you don't turn corrupt and make a form, carving a figure 17 that looks male or female, or looks like a prowling animal or a flying bird 18 or a slithering snake or a fish in a stream. 19 And also carefully guard yourselves so that you don't look up into the skies and see the sun and moon and stars, all the constellations of the skies, and be seduced into worshiping and serving them. God set them out for everybody's benefit, everywhere.
Matthew Henry's Commentary on Deuteronomy 4:15-19
Commentary on Deuteronomy 4:1-23
(Read Deuteronomy 4:1-23)
The power and love of God to Israel are here made the ground and reason of a number of cautions and serious warnings; and although there is much reference to their national covenant, yet all may be applied to those who live under the gospel. What are laws made for but to be observed and obeyed? Our obedience as individuals cannot merit salvation; but it is the only evidence that we are partakers of the gift of God, which is eternal life through Jesus Christ, Considering how many temptations we are compassed with, and what corrupt desires we have in our bosoms, we have great need to keep our hearts with all diligence. Those cannot walk aright, who walk carelessly. Moses charges particularly to take heed of the sin of idolatry. He shows how weak the temptation would be to those who thought aright; for these pretended gods, the sun, moon, and stars, were only blessings which the Lord their God had imparted to all nations. It is absurd to worship them; shall we serve those that were made to serve us? Take heed lest ye forget the covenant of the Lord your God. We must take heed lest at any time we forget our religion. Care, caution, and watchfulness, are helps against a bad memory.