“But how could this be?”

“Ānanda, it’s when a mendicant focuses thus: ‘This is peaceful; this is sublime—that is, the stilling of all activities, the letting go of all attachments, the ending of craving, fading away, cessation, extinguishment.’ That’s how a mendicant might gain a state of immersion like this. They wouldn’t focus on the eye or sights, ear or sounds, nose or smells, tongue or tastes, or body or touches. … And they wouldn’t focus on what is seen, heard, thought, known, attained, sought, or explored by the mind. Yet they would focus.”

Numbered Discourses 11.9 1. Dependence With Sandha