Natural peace and contentment is knowing yourself as the wide open space in which thoughts come and go, rather than the separate "thinker" or "controller" of those thoughts. You don't have thoughts - you naturally provide the space, the home, the resting place, for them.
Since you can notice thoughts, be aware of them, it's clear that thoughts cannot define, limit or contain you. If they could, you'd never be able to say "that's a thought".
Just behind, around the edges, and infusing every thought, the unspeakable vastness of you.