A common analogy about mindfulness I hear about is that the wisdom is like the sun. It is always shining there, but is frequently clouded. Your job is to avoid as much cloud as possible, and when there is no cloud left, you are enlightened.
Where is this analogy first use? Is there a sutta for this? If not, and if you have heard about this too, can you name the source that you first knew it?
it is not exactly what you want, but first there is this
"Just as, monks, from time to time a strong wind scatters and causes to vanish a great mass of clouds that has arisen, even so a monk who cultivates and makes much of the seven limbs of wisdom from time to time scatters and causes to vanish the ill, unprofitable states that rise and rise again.
http://obo.genaud.net/dhamma-vinaya/pts/sn/05_mv/sn05.46.099-110.wood.pts.htm#p107
http://obo.genaud.net/dhamma-vinaya/pts/sn/05_mv/sn05.46.099-110.wood.pts.htm#p106
what you seek is found in Theragatha
Who once was heedless,[1] but later is not, brightens the world
like the moon set free from a cloud.His evil-done deed[2] is replaced with skillfulness: he brightens the world like the moon set free from a cloud.
http://obo.genaud.net/dhamma-vinaya/ati/kd/thag/thag.255.than.ati.htm
and in MN http://obo.genaud.net/dhamma-vinaya/bd/mn/mn.112.olds.bd.htm
Then, by letting go these five bindups, afflictions of the heart, crippling to wisdom, separating myself from sense pleasures, separating myself from unskillful things, with rethinking, with reminiscing,[13] there came the pleasurable Enthusiasm born of solitude inhabiting the first burning.
Then, rethinking and reminiscing calmed, inwardly impassive, become unified in heart, without rethinking, without reminiscing, there came the pleasurable Enthusiasm born of serinity inhabiting the second burning.
Then, Enthusiasm fading, living detached, recollected and self-aware, there came the experiencing of the bodily pleasure inhabiting the third burning of which the Aristocrats delcare:
'Detached, recollected, he lives happily.'
Then, letting go of pleasure, letting go of pain, their precursers in mental ease and discomfort having found their own way home, without pain or pleasure, there came the utter purity of the detached mind inhabiting the fourth burning.
Then, thus with calm heart, pure, clean, debtless, without afflictions, become soft, capable, steadfast, unshakable, the heart bent down to knowledge of the eradication of the corruptions.
Then the knowledge: 'This is pain' emerged as though a splendid light from a dark cloud, the knowledge: 'This is the source of pain' emerged as though a splendid light from a dark cloud, the knowledge: 'This is the end to pain' emerged as though a splendid light from a dark cloud, the knowledge: 'This is the way to walk to the end of pain' emerged as though a splended light from a dark cloud.
Then the knowledge: 'This is corruption' emerged as though a splended light from a dark cloud, the knowledge: 'This is the source of corruption' emerged as though a splended light from a dark cloud, the knowledge: 'This is the end to corruption' emerged as though a splended light from a dark cloud, the knowledge: 'This is the way to walk to the end of corruption' emerged as though a splended light from a dark cloud.
When I knew thus, saw thus, I was freed in heart from the corruption of sense pleasures, freed in heart from the corruption of living, freed in heart from the corruption of blindness.
In freedom I thought: "I am free' and had the knowledge:
'Birth: left behind, carrying on as Brahma: finished, duty's doing: done, no further it'n-n-at'n is to be known for me'.
Even so, my friends, thus knowing, seeing, with regard to this body with consciousness and all external signs, I say that 'Bias towards me- my-making is uprooted.'
http://obo.genaud.net/dhamma-vinaya/pts/an/10_tens/an10.015.wood.pts.htm
You also have the variant with the rain cloud http://obo.genaud.net/a/dhamma-vinaya/wp/sn/05_mv/sn05.45.149-160.bodh.wp.htm
Householder Ooker,
The sun is only something that western people seek for. On the most populated places on earth sun means heat and burning the skin. Out of that reason one would not easy find sun as something desirable in the teachings, since it's all about getting good and ending the burning.
There are already certain samples in householder user12901's answer and maybe some more in relation with the moon: set free from a cloud {heedfulness, skillfulness} Dhp 172, Dhp 382, Iti 74. Sun is seldom used and wisdom is nothing that is inherent but used the cast off the defilement. Wisdom is a tool, not the aim for liberation. Searching for similes works fine here, in Upasaka John Bullitt's generous collection.
Clouds are usually used for defilements of mind or hindrances.
It's worthy to note that Wisdom is actually "just a tool" and not the aim of the holy life, the path, but simply liberation incl. panna-vimutti, wisdom-liberation.
Sun and cloud similes are very western and so found everywhere incl. teaser for "Buddhism", but again, nothing that people would desire, a cloud-less day, in not northern or far southern lands but shadow.
(Note that this is not given for trade, exchange, stacks, entertainment and akusala deeds, but as a share of merits and to continue such for release)
