A eunuch of great authority (eunouchos dunastēs). Eunuchs were often employed by oriental rulers in high posts. Dynasty comes from this old word dunastēs used of princes in Luk 1:52 and of God in 1Ti 6:15. Eunuchs were not allowed to be Jews in the full sense (Deu 23:1), but only proselytes of the gate. But Christianity is spreading to Samaritans and to eunuchs.
Candace (Kandakēs). Not a personal name, but like Pharaoh and Ptolemy, the title of the queens of Ethiopia. This eunuch apparently brought the gospel to Ethiopia.
Treasure (gazēs). Persian word, common in late Greek and Latin for the royal treasure, here only in the N.T.
For to worship (proskunēsōn). Future active participle expressing purpose, a common idiom in the ancient Greek, but rare in the N.T. (Robertson, Grammar, p. 1128).