In "Summer Time Rendering," the theme of redemption is depicted through the protagonist's journey of seeking forgiveness, making amends for past mistakes, and ultimately finding redemption. The story emphasizes the importance of self-reflection, acceptance, and growth as key elements in the process of seeking redemption for one's actions. Through the character arcs and development, the narrative showcases the complexities of navigating through past regrets and the potential for healing and transformation through these experiences.