C.S. Lewis, in "The Screwtape Letters," conveys a profound perspective on the nature of time, emphasizing the distinction between the past, present, and future. He describes the future as the most transient and temporary aspect of time, in contrast to the past, which is static and fixed. The future is filled with uncertainty and potential, constantly shifting and never fully realized.

According to Lewis, while the present moment is vibrant and illuminated with the essence of existence, it is the future that embodies change and unpredictability. This highlights the importance of living in the present rather than being preoccupied with what is to come, as the future is elusive and distinct from the eternal nature of the past and present.