sn.46.35 Saṁyutta Nikāya (Linked Discourses)

Improper Attention

“Mendicants, when you attend improperly, sensual desire, ill will, dullness and drowsiness, restlessness and remorse, and doubt arise, and once arisen they increase and grow.”
“Mendicants, when you attend properly, the awakening factors of mindfulness, investigation of principles, energy, rapture, tranquility, immersion, and equanimity arise, and once they’ve arisen, they’re fully developed.”