Quote from A Honed and Heavy Ax
The Buddha said it is impossible to have liberating insight as long as one or more of the five hindrances are infecting the mind (AN 5.51). These mental obstacles are grouped as 1) sensual desire, an attraction to and preoccupation with the world of the five senses, 2) anger, aversion, frustration, disappointment, 3) dullness or drowsiness, 4) restlessness, remorse, anxiety, guilt and 5) doubt. If any of these or related states are present, the heart will be agitated and confused. The five hindrances make the mind rigid, weak and unworkable. Ignorance feeds on the five hindrances. They are the cause and condition for deluded understanding, and without the inner stillness and silence of samatha (dhyana-samadhi) it is almost certain that the mind is still being haunted by their influence (MN 68.6). .