His name now became Gaius Julius Caesar Octavianus. In 27BC, in return for services rendered, the Roman Senate conferred on him the name ‘Augustus’. From this time he was granted powers that gave him imperial status, including supreme command over the army. In order to maintain the loyalty of his soldiers it was essential to be able to pay them, and the revenues for this purpose had to be levied from all the parts of the Empire (“all the world”).
This, then, was the reason for the decree for the census referred to in Luke 2:1. Augustus died in AD14. His name is connected to the Latin verb augeo, meaning ‘increase, enlarge’, and giving us words like ‘augment’, ‘author’ ‘auxiliary’. The month of August is named after Augustus, as the month of July was named after Julius Caesar. With Augustus, the name ‘Caesar’ becomes an imperial title rather than merely a family name.