In Miriam Toews' "A Complicated Kindness," the quote highlights the themes of human imperfection and moral shortcomings. It emphasizes that even our best efforts can be flawed and inadequate, comparing them to filthy rags. This reflects the idea that human righteousness is often superficial and insufficient in the face of true moral integrity.

The quote also speaks to the transient nature of life and the inevitable decline everyone faces. It suggests that, like a leaf fading or wind carrying away our wrongdoings, human life and dignity are fragile and fleeting, reminding us of the importance of humility and acknowledgment of our limitations.