[830] Which phenomena (dhammā) belong to the formless sphere (arūpāvacara)?
Making the devas who have reached the sphere of infinity of space (ākāsānañcāyatana) the limit below, and making the devas who have reached the sphere of neither perception nor non-perception (nevasaññānāsaññāyatana) the inclusive limit above: whatever phenomena within this interval have their range here and are included here — the phenomena consisting of mind (citta) and mental factors (cetasika) of one who has attained [the attainment], or of one who has been reborn [there], or of one who dwells in happiness in this very life (diṭṭhadhammasukhavihārī) — these phenomena belong to the formless sphere.
Which phenomena do not belong to the formless sphere?
Those belonging to the sensual sphere (kāmāvacara), those belonging to the form sphere (rūpāvacara), and the unincluded (apariyāpanna) — these phenomena do not belong to the formless sphere.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.