Bhagavad Gita
Chapter 12 · Verse 15
यस्मान्नोद्विजते लोको लोकान्नोद्विजते च यः। हर्षामर्षभयोद्वेगैर्मुक्तो यः स च मे प्रियः॥
yasmān nodvijate loko lokān nodvijate ca yaḥ, harṣāmarṣa-bhayodvegair mukto yaḥ sa ca me priyaḥ
A quiet kind of strength: being someone who doesn't unsettle others, and who has enough steadiness not to be easily unsettled by them either.
Be someone the world doesn't unsettle, and who doesn't unsettle the world.