Acts in front of these empire builders (6)
I believe the answer is:
romans
I believe this clue is a double definition.
'acts in front of these' is the first definition.
(Acts comes before Romans in the New Testament)
'empire builders' is the second definition.
(I've seen this before)
(Other definitions for romans that I've seen before include "Ancient Italians" , "'Friends, . . . . . ., countrymen, lend me your ears' (Julius Caesar)" , "Empire builders" , "New Testament book" , "Classical Italians" .)