Especially because thou art expert (malista gnōstēn onta se). Or like the margin, “because thou art especially expert,” according as malista is construed. Gnōstēn is from ginōskō and means a knower, expert, connoisseur. Plutarch uses it and Deissmann (Light, etc., p. 367) restores it in a papyrus. Agrippa had the care of the temple, the appointment of the high priest, and the care of the sacred vestments. But the accusative onta se gives trouble here coming so soon after sou (genitive with epi). Some MSS. insert epistamenos or eidōs (knowing) but neither is genuine. Page takes it as “governed by the sense of thinking or considering.” Knowling considers it an anacoluthon. Buttmann held it to be an accusative absolute after the old Greek idiom. Tuchon is such an instance though used as an adverb (1Co 16:6). It is possible that one exists in Eph 1:18. See other examples discussed in Robertson’s Grammar, pp. 490f.
Customs and questions (ethōn te kai zētēmatōn). Both consuetudinum in practicis and quaestionum in theoreticis (Bengel). Agrippa was qualified to give Paul an understanding and a sympathetic hearing. Paul understands perfectly the grand-stand play of the whole performance, but he refused to be silent and chose to use this opportunity, slim as it seemed, to get a fresh hearing for his own case and to present the claims of Christ to this influential man. His address is a masterpiece of noble apologetic.
Patiently (makrothumōs). Adverb from makrothumos. Only here in the N.T., though makrothumia occurs several times. Vulgate has longanimiter. Long spirit, endurance, opposite of impatience. So Paul takes his time.