The Chapter on Brightness

AN 4.141 Brightness Ābhāsutta

"Mendicants, there are these four kinds of brightness. What four? The brightness of the moon, sun, fire, and wisdom. These are the four kinds of brightness. The best of these four kinds of brightness is the brightness of wisdom."

AN 4.142 Radiance Pabhāsutta

"Mendicants, there are these four kinds of radiance. What four? The radiance of the moon, sun, fire, and wisdom. These are the four kinds of radiance. The best of these four kinds of radiance is the radiance of wisdom."

AN 4.143 Light Ālokasutta

"Mendicants, there are these four lights. What four? The lights of the moon, sun, fire, and wisdom. These are the four lights. The best of these four lights is the light of wisdom."

AN 4.144 Shining Obhāsasutta

"Mendicants, there are four kinds of shining. What four? The shining of the moon, sun, fire, and wisdom. These are the four kinds of shining. The best of these four kinds of shining is the shining of wisdom."

AN 4.145 Lamps Pajjotasutta

"Mendicants, there are these four lamps. What four? The lamps of the moon, sun, fire, and wisdom. These are the four lamps. The best of these four lamps is the lamp of wisdom."

AN 4.146 Times (1st) Paṭhamakālasutta

"Mendicants, there are these four times. What four? A time for listening to the teaching, a time for discussing the teaching, a time for serenity, and a time for discernment. These are the four times."

AN 4.147 Times (2nd) Dutiyakālasutta

"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.

It's like when the heavens rain heavily on a mountain top, and the water flows downhill to fill the hollows, crevices, and creeks. As they become full, they fill up the pools. The pools fill up the lakes, the lakes fill up the streams, and the streams fill up the rivers. And as the rivers become full, they fill up the ocean.

In the same way, when these four times are rightly developed and progressed, they gradually lead to the ending of defilements."

AN 4.148 Bad Conduct Duccaritasutta

"Mendicants, there are these four kinds of bad conduct by way of speech. What four? Speech that's false, divisive, harsh, or nonsensical. These are the four kinds of bad conduct by way of speech."

AN 4.149 Good Conduct Sucaritasutta

"Mendicants, there are these four kinds of good conduct by way of speech. What four? Speech that's true, harmonious, gentle, and thoughtful. These are the four kinds of good conduct by way of speech."

AN 4.150 Essentials Sārasutta

"Mendicants, there are these four essentials. What four? Ethics, immersion, wisdom, and freedom are essentials. These are the four essentials."