SuttaCentral
Hey all,
I would love to find this teaching, any idea what sutta it might be in?
The Buddha didn’t embrace all good spiritual practices all the time, but advised paying attention to their helpful or harmful effects. (Wish I could recall where to find that sutta; any sutta hunters available to add the link? Seems like maybe Ananda explained this to someone.)
MN 2 perhaps?
Bhikkhus, there are taints that should be abandoned by seeing. There are taints that should be abandoned by restraining. There are taints that should be abandoned by using. There are taints that should be abandoned by enduring. There are taints that should be abandoned by avoiding. There are taints that should be abandoned by removing. There are taints that should be abandoned by developing.
There’s also AN 4.147 (and a bit shorter AN 4.146):
AN4.147:1.1: “Mendicants, when these four times are rightly developed and progressed, they gradually lead to the ending of defilements.
What four?
A time for listening to the teaching, a time for discussing the teaching, a time for serenity, and a time for discernment.
There’s also AN 3.102 (with the simile of the goldsmith):
AN3.102:1.1: “Mendicants, a mendicant committed to the higher mind should focus on three foundations from time to time:
the foundation of immersion, the foundation of exertion, and the foundation of equanimity.
If a mendicant dedicated to the higher mind focuses solely on the foundation of immersion, it’s likely their mind will incline to laziness.
If they focus solely on the foundation of exertion, it’s likely their mind will incline to restlessness.
If they focus solely on the foundation of equanimity, it’s likely their mind won’t properly become immersed in samādhi for the ending of defilements.
Maybe this Aggisutta SN 46.53 is the one you are looking for:
i. The sluggish mind: untimely
“On an occasion, bhikkhus, when the mind becomes sluggish, it is untimely to develop the enlightenment factor of tranquillity, the enlightenment factor of concentration, and the enlightenment factor of equanimity. For what reason? Because the mind is sluggish, bhikkhus, and it is difficult to arouse it with those things.
“Suppose, bhikkhus, a man wants to make a small fire flare up. If he throws wet grass, wet cowdung, and wet timber into it, sprays it with water, and scatters soil over it, would he be able to make that small fire flare up?”
“No, venerable sir.”
“So too, bhikkhus, on an occasion when the mind becomes sluggish, it is untimely to develop the enlightenment factor of tranquillity, the enlightenment factor of concentration, and the enlightenment factor of equanimity. For what reason? Because the mind is sluggish, bhikkhus, and it is difficult to arouse it with those things.
ii. The sluggish mind: timely
“On an occasion, bhikkhus, when the mind becomes sluggish, it is timely to develop the enlightenment factor of discrimination of states, the enlightenment factor of energy, and the enlightenment factor of rapture. For what reason? Because the mind is sluggish, bhikkhus, and it is easy to arouse it with those things.
“Suppose, bhikkhus, a man wants to make a small fire flare up. If he throws dry grass, dry cowdung, and dry timber into it, blows on it, and does not scatter soil over it, would he be able to make that small fire flare up?”
“Yes, venerable sir.”
“So too, bhikkhus, on an occasion when the mind becomes sluggish, it is timely to develop the enlightenment factor of discrimination of states, the enlightenment factor of energy, and the enlightenment factor of rapture. For what reason? Because the mind is sluggish, bhikkhus, and it is easy to arouse it with those things.
iii. The excited mind: untimely
“On an occasion, bhikkhus, when the mind becomes excited, it is untimely to develop the enlightenment factor of discrimination of states, the enlightenment factor of energy, and the enlightenment factor of rapture. For what reason? Because the mind is excited, bhikkhus, and it is difficult to calm it down with those things.
“Suppose, bhikkhus, a man wants to extinguish a great bonfire. If he throws dry grass, dry cowdung, and dry timber into it, blows on it, and does not scatter soil over it, would he be able to extinguish that great bonfire?”
“No, venerable sir.”
“So too, bhikkhus, on an occasion when the mind becomes excited, it is untimely to develop the enlightenment factor of discrimination of states, the enlightenment factor of energy, and the enlightenment factor of rapture. For what reason? Because the mind is excited, bhikkhus, and it is difficult to calm it down with those things.
iv. The excited mind: timely
“On an occasion, bhikkhus, when the mind becomes excited, it is timely to develop the enlightenment factor of tranquillity, the enlightenment factor of concentration, and the enlightenment factor of equanimity. For what reason? Because the mind is excited, bhikkhus, and it is easy to calm it down with those things.
“Suppose, bhikkhus, a man wants to extinguish a great bonfire. If he throws wet grass, wet cowdung, and wet timber into it, sprays it with water, and scatters soil over it, would he be able to extinguish that great bonfire?”
“Yes, venerable sir.”
“So too, bhikkhus, on an occasion when the mind becomes excited, it is timely to develop the enlightenment factor of tranquillity, the enlightenment factor of concentration, and the enlightenment factor of equanimity. For what reason? Because the mind is excited, bhikkhus, and it is easy to calm it down with those things.
“But mindfulness, bhikkhus, I say is always useful.”
SN 46.53 is a key sutta from the view it describes the dynamics of the factors of awakening and so presents a breakthrough from the verbal to a new level of understanding— how the factors behave as energy. The mind has energy states passive or active, and these must be matched with their opposite counterparts which function as groups with a simple causal sequence, investigation is the initiator.
MN 19 shows division is necessary, and describes the two different states, active and passive. There is a scale difference between ‘pleasant abiding’ and ‘sluggishness’:
"“Just as in the last month of the Rains, in the autumn season when the crops are ripening, a cowherd would look after his cows: He would tap & poke & check & curb them with a stick on this side & that. Why is that? Because he foresees flogging or imprisonment or a fine or public censure arising from that [if he let his cows wander into the crops]. In the same way I foresaw in unskillful qualities drawbacks, degradation, & defilement, and I foresaw in skillful qualities rewards related to renunciation & promoting cleansing.”
""Just as in the last month of the hot season, when all the crops have been gathered into the village, a cowherd would look after his cows: While resting under the shade of a tree or out in the open, he simply keeps himself mindful of ‘those cows.’ In the same way, I simply kept myself mindful of ‘those mental qualities.’
The sutta describes investigation and its results as being the active process which ‘promotes unbinding.’
Hello. Maybe there is a sutta. There are statements that distinguish between different teachings for different audiences, such as:
Mendicants, these two extremes should not be cultivated by one who has gone forth.
SN 56.11 (SuttaCentral)
Householder, it does not occur to us to teach such a Dhamma talk to white-clothed laypeople. Rather, we teach like this to those gone forth.
MN 143 (SuttaCentral)
Ascetics and brahmins served by a gentleman in these five ways show compassion to him in five ways. They keep him from doing bad. They support him in doing good. They think of him with kindly thoughts. They teach him what he does not know. They clarify what he’s already learned. They explain the path to heaven.
DN 31 (SuttaCentral)
Then Sāriputta thought: “These brahmins are devoted to the Brahmā realm. Why don’t I teach him a path to the company of Brahmā?”
MN 97 (SuttaCentral)
I think analysis of open questions by certain audiences will find different teachings give to different audiences, such as SN 55.7 (SuttaCentral) vs SN 55.53 (SuttaCentral) vs AN 3.52 (SuttaCentral) vs AN 5.33 (SuttaCentral) etc.
Possibly AN 5.159 offers general principles: 
Ānanda, it’s not easy to teach Dhamma to others. You should establish five things in yourself before teaching Dhamma to others. What five?
You should teach Dhamma to others thinking: ‘I will teach step by step.’ …
‘I will teach explaining my methods.’ … (explaining the sequence of cause & effect: Thanissaro)
‘I will teach out of kindness.’ …
‘I will not teach while secretly hoping to profit.’ …
‘I will teach without hurting myself or others.’
Also AN 9.5
The best sort of kindly speech is to teach the Dhamma again and again to someone who is engaged and who lends an ear.