[RobertK]

In the same way, there are some cases where a monk — wise, experienced, familiar with his pasture, skilled in being quite withdrawn from sensuality, withdrawn from unskillful qualities, and entering & remaining in the first jhana: rapture & pleasure born from withdrawal, accompanied by directed thought & evaluation — sticks with that perceptual image (nimitta), develops it, pursues it, & establishes himself firmly in it.

http://www.accesstoinsight.org/tipitaka/an...9.035.than.html

"And what is the food for the arising of unarisen concentration as a factor for Awakening, or for the growth & increase of concentration... once it has arisen? There are perceptual images (nimitta) for calm, perceptual images for non-distraction. To foster appropriate attention to them: This is the food for the arising of unarisen concentration as a factor for Awakening, or for the growth & increase of concentration... once it has arisen.

http://www.accesstoinsight.org/tipitaka/sn...6.051.than.html

Sunaga (Thag 1.85) {v. 85} [go up]

Adept in a perceptual image (nimitta) for the mind,
sensing the savor of solitude,
practicing jhana,
masterful, mindful,
you'd attain a pleasure
not of the flesh.

http://www.accesstoinsight.org/tipitaka/kn...1.00x.than.html