This is the post #11 of the Calvin's Institutes summary series.
Making of idols to represent god(s) is a common folly among peoples, but any kind of visual representations of God (pictures as well as sculptures, hence, the Eastern Orthodox Christians are inexcusable in this) is forbidden by Scripture. This is because any visual depiction takes away from God glory and misleads everyone who looks at them. Some visual items in the OT about God or His presence does not permit us to make any images ourselves.
There had been significant figures in church history who taught images were to be used for Christian worship, and/or images of saints to be venerated. Their teaching flatly contradicts the bible's teaching (eg. Jer. 10:8, Hab 2:18), and good doctors of the church, such as Augustine, agree with the biblical teaching. The papists claim that images are useful teaching aids for the uneducated people, but the images actually don't help at all but mislead them greatly. Also, when the church is teaching the biblical doctrines properly by preaching of the Word and through the mandated images, that are the two sacraments (baptism and the Lord's Supper), everyone will know God much better and glorify Him.
People create images of god(s) because of their pride, preferring to worship their own imaginations rather than what God has revealed in the Word. Most people would begin by simply saying that the images are not in fact God, but God is simply represented or it helps people to focus their thoughts on God Himself. This is foolishness. We are more corrupt than we think or want to think of ourselves. Once we begin looking to images to help us think about God, we will inevitably be led to think of the images as God. This includes images of the saints.
Images and paintings can be used in a proper way in churches. When they show historical events, rather than simply some human figures, they can be used to help people understand such events better. However, there are ways when images are used without any teaching values. It is only when the teachings in the church is weak and sickly that images proliferated. Often the Scripture is ignored or misused by those who argue for the uses of images in churches.