After issuing a warning regarding covetousness, Jesus spoke this parable to the crowd of listeners. He wanted them to clearly understand His point about one's life not consisting in the abundance of earthly possessions.
Let it be noted that the rich man in the parable was not guilty of thievery or extortion. His wealth came to him honestly as a blessing from God. However, the rich man's words betrayed his sins. He used the word "I" six times, highlighting an attitude of selfishness and pride. Additionally, he used the word "my" five times, exposing a covetous spirit. This rich man Jesus described thought of no one but himself. As a side note, if a person today speaks excessively about himself, he is no doubt also suffering from the same sins.
The rich man wondered to himself - "What shall I do, since I have no room to store my crops?" The question itself is a good one, but he directed the inquiry to the wrong individual. He should have asked God what He would have him to do! In pulling down his barns and building greater ones, the rich man was not directly injuring anyone, and he wasn't doing anything unkind.
So, where is the problem? The problem lies in the fact that he did not use his wealth to help others, namely the poor (cf. Matt. 19:21; Luke 18:22). He was a poor steward of God's blessings in that regard. He proposed to selfishly hoard everything for his own comfort and pleasure. The rich man was planning to enjoy ease and was not concerned about the state of anyone else. He intended to "eat, drink, and be merry," whether anyone else had the necessities of life or not. He arrogantly believed his wealth would guarantee him a happy life for a long time, but it could not guarantee him even one day! Friends, may we never forget this truth!
Luke 12:20 reveals the mind of God toward such thinking and living. God called the rich man a "fool", though the world would call him a wise and successful farmer. He was a fool in several ways: (1) he hoarded his goods instead of using them for the benefit of others (cf. 16:19ff), (2) because of his great possessions, he deceived himself into thinking that he owned time also (cf. Prov. 27:1; James 4:13-15), (3) he thought he could satisfy the hunger of his "soul" with the food of the body, and (4) he directed his own soul in a way that did not recognize God's ultimate authority over him.
Those today who lay up physical treasure for themselves on Earth and are not rich toward God are also fools. The sin is not in being rich, for Abraham and Job were both wealthy, godly men. The sin is in making one's possessions his treasure (cf. Luke 12:34). When we are in love with money and things, we will fail to be "rich toward God." In other words, we will selfishly fail to use our resources and time to help those in need and accomplish the good that we should for God's kingdom. Those who love themselves and their possessions more than others are foolishly failing to "seek first the kingdom of God" (cf. 12:31). They do such to their own eternal demise.