One in whom thirst is exhausted is purified, becomes Brahman. This is immortality, without stain; the meditator meditates on the divine.

Brahmabhūto — made Brahman. The Buddha uses brahmanic language but empties it of theistic content: Brahman is not an external god, it is the state of purity resulting from the extinction of thirst.

Visaññutaṁ — without stain, without impurity. Meditation (jhāyī) on the divine (brahma) is the practice that maintains this state.