[986] **At the proper time — he, rightly investigating the Dhamma at the proper time (kālena so sammā dhammaṃ parivīmaṃsamāno):** "at the proper time" means: when the mind (citta) is restless, it is the time for serenity (samatha); when the mind is concentrated, it is the time for insight (vipassanā).
At the proper time he exerts the mind, and at another time he restrains it;
at the proper time he gladdens it, at the proper time he composes the mind;
at the proper time he looks on with equanimity — that meditator (yogī) is skilled in the times.
At what time should there be exertion? At what time restraint?
What is the time for gladdening? And what is the time for serenity like?
How does one point out to the meditator the time for equanimity toward the mind?
When the mind is slack, there should be exertion; when it is restless, restraint;
a mind that has become joyless one should gladden at that very moment.
When the mind is gladdened, neither slack nor restless,
that is the time for serenity; the mind should delight within.
By this very method, when the mind becomes concentrated,
then one should look on the concentrated mind with equanimity by means of wisdom (paññā).
Thus the steadfast one who knows the times, who understands the times, skilled in the times,
should from time to time discern the sign (nimitta) of the mind.
Thus: "he ... at the proper time." **Rightly investigating the Dhamma:** rightly investigating the Dhamma thus, "All conditioned things (saṅkhārā) are impermanent"; rightly investigating the Dhamma thus, "All conditioned things are suffering (dukkha)"; rightly investigating the Dhamma thus, "All dhammas are not-self"; … rightly investigating the Dhamma thus, "Whatever is subject to origination, all that is subject to cessation." Thus: "rightly investigating the Dhamma."
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.