I got a couple that I re-read often:
"When you try to command a spontaneous process you stop it." - Alan Watts
"If there is no enemy within the enemy outside can do us no harm" - African proverb
"Here is the world. Beautiful and terrible things will happen. Don't be afraid." Frederick Buechner
"When we are no longer able to change a situation, we are challenged to change ourselves" - Victor Frankl
and another from Alan Watts: "When you are perfectly free to feel stuck or not stuck you are unstuck."