"When soldiers came to St John the Baptist asking what to do, he never remotely suggested that they ought to leave the army: nor did Christ when He met a Roman sergeant-major--what they called a centurion."
Centurion reenactment, Boulougne, France
GNU Free Documentation LicenseCenturion reenactment, Boulougne, France - Credit: Luc Viatour / www.Lucnix.be

In Luke 3, John the Baptist used strong words when preaching to the crowds who came to hear him, calling them a "brood of vipers" and urging them to repent. Soldiers in the crowd "asked him, 'And we, what shall we do?' And he said to them, 'Do not extort money from anyone by threats or by false accusation, and be content with your wages.'"

And in Luke 7, Christ miraculously heals a Roman centurion's servant and commends the centurion for his faith.