At Savatthi. "Monks, I will teach you the phenomena to be comprehended, as well as comprehension. Listen & pay close attention. I will speak."
"As you say, lord," the monks responded.
The Blessed One said, "And which are the phenomena to be comprehended? Form is a phenomenon to be comprehended. Feeling ... Perception ... Fabrications ... Consciousness is a phenomenon to be comprehended. These are called phenomena to be comprehended.
"And which is comprehension? Any ending of passion, ending of aversion, ending of delusion.  This is called comprehension."
See also: SN 47.38.