minister

But Jesus called them unto him, and said, Ye know that the princes of the Gentiles exercise dominion over them, and they that are great exercise authority upon them. But it shall not be so among you: but whosoever will be great among you, let him be your minister; And whosoever will be chief among you, let him be your servant: Even as the Son of man came not to be ministered unto, but to minister, and to give his life a ransom for many.

Matthew 20:25-28, KJV

And immediately the Spirit driveth him into the wilderness.And he was there in the wilderness forty days, tempted of Satan; and was with the wild beasts; and the angels ministered unto him.

Mark 1:12-13, KJV

What me your minister, for you obeys, Works under you; and to your audit comes Their distract parcels in combined sums.

Shakespeare, A Lover's Complaint

He that of greatest works is finisher Oft does them by the weakest minister

Shakespeare, All's Well That Ends Well, Act 2, Scene 1