'highest knowledge', gnosis, refers to the perfect knowledge of the Saint
(Arahat; s. ariya-puggala).
The following passage occurs frequently in the Suttas, when a monk indicates
his attainment of Holiness (arahatta): "He makes known highest knowledge
(aññam vyākaroti), thus: 'Rebirth has ceased, fulfilled is the holy life,
the task is accomplished, and there is no more of this to come.' "
The 'ability of highest knowledge' (aññ' indriya = aññā-indriya; s.
indriya), however, is present in six of the
eight stages of holiness, that is, beginning with the fruition of Stream-Winning
(sotāpatti-phala) up to the path of Holiness (arahatta-magga).
See Dhs. (PTS) 362-364, 505, 553; Indriya Vibhanga; "Path" 162.