What does it mean to be foolish in the context of the rich fool?

In the context of the rich fool, folly is marked by a disregard for spiritual realities and a focus on self-gratification. The man in the parable lived without regard for his soul's well-being and assumed life was purely in his control (Luke 12:20). This shows a classic error of humanity—misplacing our identity and worth in material rather than spiritual matters. To be wise unto salvation means recognizing our ultimate accountability before God and living accordingly, understanding that our time on earth is temporary and that true joy and fulfillment come from faith in Christ, not the accumulation of possessions.