Pariñañeyyatasūra

Suttapiṭaka · Saṁyuttanikāya · Khandhavaggasaṁyutta · Vol. 17 · Section 290

[290] "And what, bhikkhus, are the dhammas that should be fully understood (pariññeyyā dhammā)? Form (rūpa), bhikkhus, is a dhamma that should be fully understood; feeling (vedanā), perception (saññā) … volitional formations (saṅkhārā) … Consciousness (viññāṇa) is a dhamma that should be fully understood. These, bhikkhus, are called the dhammas that should be fully understood."

English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.

This passage also appears in 1 other place

Vol. 17 · Section 54 — Chandarāgasutta