1At Sāvatthī. Standing to one side, that devata recited this verse in the presence of the Blessed One:

2v.17 "Those who dwell deep in the forest,
Peaceful, leading the holy life,
Eating but a single meal a day:
Why is their complexion so serene?" [n.18] Spk: This verse was spoken by an earth-bound deva who dwelt in that forest. Each day he would see the bhikkhus who inhabited the forest sitting in meditation after their meal. As they sat, their minds would become unified and serene, and the serenity of their minds would become manifest in their complexion (vaṇṇa). Puzzled that they could have such serene faces while living under these austere conditions, the deva came to the Buddha to inquire into the cause. The facial complexion (mukhavaṇṇa) or complexion of the skin (chavivaṇṇa) is understood to indicate success in meditation; see SN21.3, SN28.1; and Khandaka 1.

The Blessed One:

3v.18 "They do not sorrow over the past,
Nor do they hanker for the future.
They maintain themselves with what is present:
Hence their complexion is so serene.

4v.19 "Through hankering for the future,
Through sorrowing over the past,
Fools dry up and wither away
Like a green reed cut down."

1Sāvatthinidānaṁ. Ekamantaṁ ṭhitā kho sā devatā bhagavantaṁ gāthāya ajjhabhāsi:

2"Araññe vihārantānaṁ,
santānaṁ brahmacārinaṁ;
Ekabhattaṁ bhuñjamānānaṁ,
kena vaṇṇo pasīdatī"ti.

3"Atītaṁ nānusocanti,
nappajappanti nāgataṁ;
Paccuppannena yāpenti,
tena vaṇṇo pasīdati.

4Anāgatappajappāya,
atītassānusocanā;
Etena bālā sussanti,
naḷova harito luto"ti.