[570] "Bhikkhus, on an occasion when the mind (citta) is sluggish, that is the time for developing the investigation of dhammas as a factor of awakening (dhammavicaya-sambojjhaṅga), the time for developing the energy factor of awakening, the time for developing the rapture factor of awakening. For what reason? Because a sluggish mind, bhikkhus, is easily roused up by these dhammas.
"Suppose, bhikkhus, a man wishing to make a small fire blaze up: he would throw dry grass upon it, throw dry cow dung upon it, throw dry sticks upon it, give it a blast of breath from his mouth, and would not scatter dust upon it. Would that man be able to make that small fire blaze up?"
"Yes, venerable sir."
"Even so, bhikkhus, on an occasion when the mind is sluggish, that is the time for developing the investigation of dhammas factor of awakening, the time for developing the energy factor of awakening, the time for developing the rapture factor of awakening. For what reason? Because a sluggish mind, bhikkhus, is easily roused up by these dhammas."
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.