The biblical teaching about idolatry is particularly helpful for evangelism in a postmodern context. The typical way that Christians define sin is to say that it is breaking God’s law. Properly explained, of course, that is a good and sufficient definition. But the law of God includes both sins of omission and of commission, and it includes the attitudes of the heart as well as behavior. Those wrong attitudes and motivations are usually inordinate desires—forms of idolatry. However, when most listeners hear us define sin as “breaking God’s law” all the emphasis in their minds falls on the negative (sins of commission) and on the external (behaviors rather than attitudes.) There are significant reasons, then, that “law-breaking” isn’t the best way to first describe sin to postmodern listeners....
There is another reason we need a different definition of sin for postmodern people. They are relativists, and the moment you say, “Sin is breaking God’s moral standards,” they will retort, “Well, who is to say whose moral standards are right? Everyone has different ones! What makes Christians think that theirs are the only right set of moral standards?” The usual way to respond to this is to become sidetracked from your presentation of sin and grace into an apologetic discussion about relativism. Of course, postmodern people must be strongly challenged about their mushy view of truth, but I think there is a way to move forward and actually make a credible and convicting gospel presentation before you get into the apologetic issues. I do it this way, I take a page from Kierkegaard’s The Sickness Unto Death and I define sin as building your identity—your self-worth and happiness—on anything other than God. Instead of telling them they are sinning because they are sleeping with their girlfriends or boyfriends, I tell them that they are sinning because they are looking to their careers and romances to save them, to give them everything that they should be looking for in God. This idolatry leads to drivenness, addictions, severe anxiety, obsessiveness, envy of others, and resentment.
More info...Talking About Idolatry in a Postmodern Age
Moral aspect
Considered in itself, idolatry is the greatest of mortal sins. For it is, by definition, an inroad on God's sovereignty over the world, an attempt on His Divine majesty, a rebellious setting up of a creature on the throne that belongs to Him alone. Even the simulation of idolatry, in order to escape death during persecution, is a mortal sin, because of the pernicious falsehood it involves and the scandal it causes. Of Seneca who, against his better knowledge, took part in idolatrous worship, St. Augustine says: "He was the more to be condemned for doing mendaciously what people believed him to do sincerely". The guilt of idolatry, however, is not to be estimated by its abstract nature alone; the concrete form it assumes in the conscience of the sinner is the all-important element. No sin is mortal — i.e. debars man from attaining the end for which he was created — that is not committed with clear knowledge and free determination. But how many, or how few, of the countless millions of idolaters are, or have been, able to distinguish between the one Creator of all things and His creatures? and, having made the distinction, how many have been perverse enough to worship the creature in preference to the Creator? — It is reasonable, Christian, and charitable to suppose that the "false gods" of the heathen were, in their conscience, the only true God they knew, and that their worship being right in its intention, went up to the one true God with that of Jews and Christians to whom He had revealed Himself. "In the day when God shall judge the secrets of men by Jesus Christ . . . . . the gentiles who have not the law, shall be judged by their conscience" (Romans 2:14-16). God, who wishes all men to be saved, and Christ, who died for all who sinned in Adam, would be frustrated in their merciful designs if the prince of this world were to carry off all idolaters.
Causes
Idolatry in its grosser forms is so far removed from the Christianized mind that it is no easy matter to account for its origin. Its persistence after gaining a first footing, and its branching out in countless varieties, are sufficiently explained by the moral necessity imposed on the younger generation to walk in the path of their elders with only insignificant deviations to the right or to the left. Thus Christian generations follow upon Christian generations; if sects arise they are Christian sects. The question as to the first origin of idolatry is thus answered by St. Thomas:
"The cause of idolatry is twofold: dispositive on the part of man; consummative on the part of the demons.
"Men were led to idolatry first by disordered affections, inasmuch as they bestowed divine honours upon someone whom they loved or venerated beyond measure. This cause is indicated in Wisdom 14:15: 'For a father being afflicted by bitter grief, made to himself the image of his son who was quickly taken away; and him who then had died as a man, he began now to worship as a god . . . ', and 14:21: 'Men serving either their affection or their king, gave the incommunicable name to stones and wood'.
"Second: By their natural love for artistic representations: uncultured men, seeing statues cunningly reproducing the figure of man, worshipped them as gods. Hence we read in Wisdom 13:11 sq., 'An artist, a carpenter has cut down a tree proper for his use in the wood . . . . . . and by the skill of his art fashioneth it and maketh it like the image of a man . . . . . and then maketh prayers to it, inquiring concerning his substance and his children or his marriage'.
"Third: By their ignorance of the true God: man, not considering the excellence of God, attributed divine worship to certain creatures excelling in beauty or virtue: Wisdom 13:1-2:' . . . . . neither by attending to the works have [men] acknowledged who was the workman, but have imagined either the fire, or the wind, or the swift air, or the circle of the stars, or the great water, or the sun and moon, to be the gods that rule the world'.
"The consummative cause of idolatry was the influence of the demons who offered themselves to the worship of erring men, giving answers from idols or doing things which to men seemed marvelous, whence the Psalmist says (Psalm 95:5): 'All the gods of the gentiles are devils'" (II-II, Q. xciv, a. 4).
The causes which the writer of Wisdom, probably an Alexandrian Jew living in the second century B.C., assigns to the idolatry prevalent in his time and environment, are sufficient to account for the origin of all idolatry. Man's love for sense images is not a vagary but a necessity of his mind. Nothing is in the intellect that has not previously passed through the senses. All thought that transcends the sphere of direct sense knowledge is clothed in material garments, be they only a word or a mathematical symbol. Likewise, the knowledge of things impervious to our senses, that comes to us by revelation, is communicated and received through the senses external or internal, and is further elaborated by comparison with notions evolved from sense perceptions; all our knowledge of the supernatural proceeds by analogy with the natural. Thus, throughout the Old Testament God reveals Himself in the likeness of man, and in the New, the Son of God, assuming human nature, speaks to us in parables and similitudes. Now, the human mind, when sufficiently ripe to receive the notion of God, is already stocked with natural imagery in which it clothes the new idea. That the limited mind of man cannot adequately represent, picture, or conceive the infinite perfection of God, is self-evident. If left to his own resources, man will slowly and imperfectly develop the obscure notion of a superior or supreme power on which his well-being depends and whom he can conciliate or offend. In this process intervenes the second cause of idolatry: ignorance. The Supreme Power is apprehended in the works and workings of nature; in sun and stars, in fertile fields, in animals, in fancied invisible influences, in powerful men. And there, among the secondary causes, the "groping after God" may end in the worship of sticks and stones. St. Paul told the Athenians that God had "winked at the times of this ignorance" during which they erected altars "To the unknown God", which implies that He had compassion on their ignorance and sent them the light of truth to reward their good intention (Acts 17:22-31). As soon as the benighted heathen has located his unknown god, love and fear, which are but the manifestations of the instinct of self-preservation, shape the cultus of the idol into sacrifices or other congenial religious practices. Ignorance of the First Cause, the need of images for fixing higher conceptions, the instinct of self-preservation — these are the psychological causes of idolatry
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