Jesus was the master teacher, and He certainly knew there were several good reasons to use parables when teaching. Let us consider three such reasons at this time.
(1) Parables present spiritual truths in an easily remembered and practical form. For example, many Bible believers can easily recall the details of "The Parable of the Lost Sheep" and explain its spiritual meaning, whereas they may not be able to remember the names of the twelve apostles. People seem to remember stories much better than isolated facts or lists.
(2) Parables are very effective in getting the listeners to mentally affirm a truth before they realize how it applies to them personally. For instance, consider II Samuel 11. That chapter records King David's most heinous sins. He lusted after Bathsheba, another man's wife, and had sexual relations with her while her husband Uriah was out fighting for the nation. The immediate consequence of the illicit union was the conception of a child. David went to great lengths in his attempts to cover up his sin, but nothing seemed to work; nothing, that is, until he arranged for Uriah to be killed--actually, murdered--in battle. The chapter closes with David taking Bathsheba to be his wife. He believes his egregious sins will not be discovered, but He was wrong, for "the thing that David had done displeased the LORD" (II Sam. 11:27). Although his sins had been successfully hidden from men, God was well aware of David's transgressions. As II Samuel 12 begins, the prophet Nathan is sent to David with a parable regarding two men. One of the men was rich, having a great abundance of flocks and herds. The other man was poor, having nothing but a lamb that he cared for like a daughter. II Samuel 12:4 reads - "And a traveler came to the rich man, who refused to take from his own flock and from his own herd to prepare one for the wayfaring man who had come to him; but he took the poor man's lamb and prepared it for the man who had come to him." David was outraged and said to Nathan - "As the LORD lives, the man who has done this shall surely die! And he shall restore fourfold for the lamb, because he did this thing and because he had no pity" (II Sam. 12:5,6). Nathan's reply devastated the king - "You are the man!" (cf. 12:7ff). The parable had worked masterfully in accomplishing its intended goal. David angrily passed judgment against the wicked rich man, but he did not see the similarity of the parable to his own circumstances. David was like the rich man who had selfishly robbed the poor man Uriah. David rightly condemned the man in the parable before realizing he was also condemning himself! He acknowledged the truth before realizing its application to himself. Truly, this is one power of parables!
(3) The effectiveness of parables is almost completely dependent upon the condition of the hearers (i.e., those interested in the truth are able to find it, but those blind to the truth remain in their ignorance). King David, although he committed some terrible sins, had a good heart (Acts 13:22). The parable was effective in his case because of such. He made the proper personal application and repented. More will be said on this point tomorrow.