This is about being one with everything.
This excerpt from the book "Dropping Ashes on the Buddha" of the Zen Master Seung Sahn Soen-Sa. helps us understand that in all our experiences when we realize that outside and inside are one, we can attain a clear mind and have the key to drop all kinds of toxic human specific delusions like arrogance, conceit, vanity, disdain...The only way to pave the road to a better, peaceful world.
One Thursday evening, after a Dharma talk at the New Haven Zen Center, a student asked Seung Sahn Soen-sa,
"It seems that in Christianity God is outside me, whereas in Zen God is inside me, so God and I are one. Is this correct?"
"Where is inside? Where is outside?"
"Inside is in here; outside is out there."
"How can you separate? Where is the boundary line?"
"I'm inside my skin, and the world is outside it."
Soen-sa said, "This is your body's skin. Where is your mind's skin?"
"Mind has no skin."
"Then where is mind?"
"Inside my head."
"Ah, your mind is very small."
(Loud laughter from the audience.)
"You must keep your mind big. Then you will understand that God, Buddha, and the whole universe fit into your mind."
Then, holding up his watch, Soen-sa said,
"Is this watch outside your mind or inside it?"