JhānavibhaṅgaAbhidhaṁbhājanīyaPaṭhamajhāna

Abhidhammapiṭaka · Vibhaṅga · Vol. 35 · Section 714

[714] Therein, which is the fourth jhāna (catuttha jhāna)? Here a bhikkhu, on the occasion when he develops the path (magga) for rebirth in the form sphere (rūpūpapatti), with the abandoning of pleasure and … enters and dwells in the fourth jhāna, the earth kasiṇa (paṭhavīkasiṇa) — on that occasion there is jhāna with two factors: equanimity (upekkhā) and one-pointedness (ekaggatā) of mind (citta). This is called the fourth jhāna. The remaining phenomena (dhammā) are associated (sampayutta) with the jhāna.

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.

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