On one occasion the Venerable Upavaṇa and the Venerable Sāriputta were dwelling at Kosambī in Ghosita’s Park. Then, in the evening, the Venerable Sāriputta emerged from seclusion and approached the Venerable Upavaṇa. He exchanged greetings with the Venerable Upavaṇa and, when they had concluded their greetings and cordial talk, he sat down to one side and said to him:
“Friend Upavaṇa, can a bhikkhu know for himself: ‘By careful attention the seven factors of enlightenment have been fully perfected by me in such a way that they lead to dwelling in comfort’?”
“A bhikkhu can know this for himself, friend Sāriputta. When arousing the enlightenment factor of mindfulness, friend, a bhikkhu understands: ‘My mind is well liberated; I have uprooted sloth and torpor and thoroughly removed restlessness and remorse. My energy has been aroused. I attend as a matter of vital concern, not sluggishly.’… When arousing the enlightenment factor of equanimity, he understands: sn.v.77 ‘My mind is well liberated; I have uprooted sloth and torpor and thoroughly removed restlessness and remorse. My energy has been aroused. I attend as a matter of vital concern, not sluggishly.’
“It is in this way, friend, that a bhikkhu can know for himself: ‘By careful attention the seven factors of enlightenment have been fully perfected by me in such a way that they lead to dwelling in comfort.’”