Dutiyamahārukkhasutta
Sāvatthiyaṁ viharati. “Seyyathāpi, bhikkhave, mahārukkho. Tassa yāni ceva mūlāni adhogamāni, yāni ca tiriyaṅgamāni, sabbāni tāni uddhaṁ ojaṁ abhiharanti. Evañhi so, bhikkhave, mahārukkho tadāhāro tadupādāno ciraṁ dīghamaddhānaṁ tiṭṭheyya. Evameva kho, bhikkhave, upādāniyesu dhammesu assādānupassino viharato taṇhā pavaḍḍhati. Taṇhāpaccayā upādānaṁ …pe… evametassa kevalassa dukkhakkhandhassa samudayo hoti.
A Great Tree (2nd)
At Sāvatthī. “Mendicants, suppose there was a great tree. And its roots going downwards and across all draw the sap upwards. Fed and fuelled by that, the great tree would stand for a long time. In the same way, there are things that fuel grasping. When you concentrate on the gratification provided by these things, your craving grows. Craving is a requirement for grasping. … That is how this entire mass of suffering originates.