Albert Barnes Commentary Nehemiah 1:11

"O Lord, I beseech thee, let now thine ear be attentive to the prayer of thy servant, and to the prayer of thy servants, who delight to fear thy name; and prosper, I pray thee, thy servant this day, and grant him mercy in the sight of this man. Now I was cupbearer to the king." — Nehemiah 1:11 (ASV)

A Persian king had numerous cup-bearers, each of whom probably discharged the office in his turn.