Below are some quotes I have found to be meaningful, sorted in their order of discovery, from the most recent to the oldest one.

You must and you will. Because you can.
— Grovyle (Pokémon Mystery Dungeon: Explorers of Sky)

When someone shows you who they are, believe them.
— Anonymous Reddit user

Age is not the number of years that you have been living. Age is the condition of your soul.
— Armen Sarkissian (Armenian physicist and politician)

Never attribute to malice that which is adequately explained by stupidity. Hanlon’s razor