"Many of the insights of the saint stem from their experience as sinners"

The quote by Eric Hoffer suggests that often those individuals who have lived through a turbulent or imperfect past are the ones who have a higher understanding of life's complexities. The reference to "saints" acknowledges those who have actually dedicated themselves to a virtuous or honorable cause, whereas the recommendation to "sinners" acknowledges those who have actually deviated from such paths in the past. Hoffer is indicating that the lessons and experiences of these "sinners" have actually given them a special point of view on life, allowing them to get higher insights that they might not have acquired otherwise. For this reason, the quote stresses how one's imperfections can be transformed into a strength and a source of knowledge.