The source of all human experience is in our own mind. The only way people are able to experience the world is through their own perception and through the lens of their own thoughts (beliefs, expectations, memories, etc.). That means, for example, it wasn't that car that cut you off that made you angry and frustrated; it was your thinking about that car cutting you off that made you angry and frustrated. Finishing a marathon after months or years of training didn't make you proud and exultant; your thinking about the fact that you finished a marathon after months or years of training made you proud and exultant.
The source of inner peace and serenity is within your own mind as well; those are what is always there underneath all the thinking, and they will become visible as you allow your thinking to slow down a bit and allow a quiet mind.
So why does it seem like certain locations or situations bring on a sense of serenity? I'm thinking right now about an actual spa, although for many people a place like the seashore or the forest or another spot in nature feels like a place of tranquility. There may be some individuality as to exactly what location or situation will bring on such feelings, but there's also a great degree of universality. (if you know anyone who has ever walked into a spa and felt more anxious, I'd love to hear about it.) It sure looks like it's the location or situation that's causing our feelings, yet we've already concluded that that's not possible. What's going on?
Well, we know it's another matter of our thinking, because it always is, but the question is how. When I go into a spa, there is an invisible thought (probably some form of conditioning) that this is a place where people come to relax, that therefore I am supposed to relax, which means I have permission to drop all the extra thoughts that usually race through my head and create a busy mind. I think "permission" is key here, because a lot of the time we have worries because we think we are supposed to. Sometimes because it seems somehow irresponsible to not worry about them. Sometimes because we somehow think worrying about them will fix them. Sometimes for other conscious or subconscious reasons. But when we get into a space that we know is supposed to be for relaxing, we know we are "allowed" to let go of the extra thoughts and worries. So we do. And we are able to experience the serenity of a quiet mind.
But what if you gave yourself permission some other place, some other time? What if you could see that worrying about something didn't fix it, didn't particularly mean you were being responsible, didn't mean you cared more, would never change the past, and could never control the future? Can you imagine giving yourself permission to have a quiet mind?
You'd never have to go to a spa again 😄