"This too will pass." 
-Farid al-Din Attar

"Freedom isn’t worth having if it doesn’t involve the freedom to make mistakes." 

-Mahatma Gandhi

"A man should be permitted to learn from his mistakes, not be condemned by them." 
-Roric Gibbs

"Everyone makes mistakes. The wise are not people who never make mistakes, but those who forgive themselves and learn from their mistakes." 

-Ajahn Brahm