“Mendicants, the Ganges river slants, slopes, and inclines to the east. In the same way, a mendicant developing and cultivating the five faculties slants, slopes, and inclines to extinguishment.

How so? It’s when a mendicant develops the faculties of faith, energy, mindfulness, immersion, and wisdom, which culminate in the removal of greed, hate, and delusion. That’s how a mendicant developing and cultivating the five faculties slants, slopes, and inclines to extinguishment.”

To be expanded for each of the different rivers as in SN45.91-102.

Six on slanting to the east,
and six on slanting to the ocean;
these two sixes make twelve,
and that’s how this chapter is recited.

"Seyyathāpi, bhikkhave, gaṅgā nadī pācīnaninnā pācīnapoṇā pācīnapabbhārā; evameva kho, bhikkhave, bhikkhu pañcindriyāni bhāvento pañcindriyāni bahulīkaronto nibbānaninno hoti nibbānapoṇo nibbānapabbhāro.

Kathañca, bhikkhave, bhikkhu pañcindriyāni bhāvento pañcindriyāni bahulīkaronto nibbānaninno hoti nibbānapoṇo nibbānapabbhāro? Idha, bhikkhave, bhikkhu saddhindriyaṁ bhāveti rāgavinayapariyosānaṁ dosavinayapariyosānaṁ mohavinayapariyosānaṁ … pe … paññindriyaṁ bhāveti rāgavinayapariyosānaṁ dosavinayapariyosānaṁ mohavinayapariyosānaṁ.

Evaṁ kho, bhikkhave, bhikkhu pañcindriyāni bhāvento pañcindriyāni bahulīkaronto nibbānaninno hoti nibbānapoṇo nibbānapabbhāro"ti.

Dvādasamaṁ.

Gaṅgāpeyyālavaggo terasamo.

Cha pācīnato ninnā,
cha ninnā ca samuddato;
Dvete cha dvādasa honti,
vaggo tena pavuccatīti.