The phrase "To err is human, but to forgive is divine" emphasizes the inherent nature of human imperfection and the extraordinary nature of forgiveness. "To err is human" acknowledges that making mistakes is a fundamental part of being human, everyone slips up or makes wrong decisions at some point. 

However, the second part, "to forgive is divine," elevates forgiveness to a sacred, almost god-like level. It suggests that while anyone can make a mistake, the ability to forgive those mistakes requires a higher, more enlightened state of being.

Forgiveness is depicted as an act of grace, one that transcends human flaws and reflects qualities often associated with the divine, such as mercy, compassion, and understanding. This phrase encourages people to embrace forgiveness, not as a sign of weakness, but as a powerful, virtuous act that brings peace and healing, showing the best of human nature when it mirrors the divine.