Answer
Broadly speaking, religious iconography is the artistic depiction of religious figures, often using symbolism. In Christianity, iconography features subjects such as Christ, Mary, or the saints. An icon is an image, usually painted on wood, that is to be venerated as a sacred object. Icons can also be engravings, mosaics, or embroideries. Although people who use icons in their worship would deny that they are practicing idolatry, it is difficult to see how “venerating” an object as “sacred” is different from idolatry.
Although Catholics also venerate religious images, iconography is most often associated with the Eastern or Orthodox Church, which teaches that the use of icons during prayer helps the worshiper know God, be united with the holy saints, and develop the fruit of the Spirit. When an Orthodox Christian enters his church, he lights a candle, makes the sign of the cross, and then kisses the icons of Christ, the Theotokos (Mary), and the saints. The church sanctuary will contain many other “Holy Icons,” as they’re called. Orthodox Christians are to have icons at home, too, and the place where the icons are kept is where family prayers are offered. Icons are seen as an illustration of the Incarnation of Christ, who left His spiritual abode to dwell in a material world. The devout also believe that an icon is a window into heaven, and their veneration passes straight to heaven, where it is received by the person depicted in the icon. Some claim that icons have facilitated miracles.
John Calvin and the other Protestant Reformers were iconoclasts; that is, they demanded the removal of icons from churches and homes. According to the Reformers, the veneration of icons and other religious artifacts was idolatry, and they were right. Any kissing of, bowing down before, or praying toward an icon is certainly idolatrous. Members of the Orthodox Church insist that they are not worshiping the paint and wood, but they admit that they give veneration, adoration, and reverence to the saints and Mary depicted in the icons. They pray to men and women; they ascribe to the icons a spiritual power that it does not possess. This is unbiblical.
There is nothing wrong with producing or enjoying religious art, per se. Viewing a painting of a biblical scene in an art gallery and admiring the artist’s technique cannot be considered idolatry. Having a picture of Jesus or of angels in one’s home may not be idolatry, either. Iconography can be studied as an art form, and icons can be viewed as fascinating examples of historical religious art. But using icons to aid one’s worship or viewing them as a “window to heaven” is definitely idolatry.
The Bible strictly forbids idolatry (Leviticus 26:1; Deuteronomy 5:9). God alone deserves to be bowed down to and worshiped. Icons are not intercessors before the throne of grace, and neither are the saints they represent. People in heaven do not have the power to hear our prayers or grant our requests. Only Jesus Christ and the Holy Spirit can intercede for us before the Father (Romans 8:26–27, 34). We should stay as far away as we can from anything that could possibly lead to idolatry.