[23] Furthermore, bhikkhus, with the abandoning of pleasure (sukha) and the abandoning of pain (dukkha), and with the previous disappearance of joy and grief (somanassa-domanassa), a bhikkhu enters and dwells in the fourth jhāna, which is neither-painful-nor-pleasant and has purity of mindfulness due to equanimity (upekkhā-sati-pārisuddhi). In this way too, bhikkhus, exertion is fruitful, striving is fruitful.
English translation from the Pali (Siam Raṭṭha edition) — under review, not for citation.