In the account of his own deeds that Augustus left to be inscribed outside his tomb, he states that in one year, as consul for the sixth time, he restored eighty two temples of the gods in the city and neglected none that needed repair at that time. The claim is exact, checkable against surviving buildings, and entirely characteristic. His public position was never that he had made something new. It was that he had put back what a century of civil war had let fall down.
The priesthoods were treated the same way. He held membership of all four great colleges, revived the Arval Brethren, an archaic body of twelve whose annual hymn was so old that the priests themselves recited it from a written text they no longer fully understood, and refilled the office of flamen Dialis, which had stood empty for seventy five years because nobody would accept its taboos. He took the office of pontifex maximus only in 12 BCE, on the death of Lepidus who held it, and made a point of having waited rather than seizing it.
The Secular Games of 17 BCE show the method in miniature. They were an ancient rite marking the passing of an age, they had not been celebrated on schedule, and the priestly college produced an interpretation of the Sibylline books that made the date correct. Horace was commissioned to write the hymn, a chorus of boys and girls sang it, and the whole thing was inscribed on stone so that it would be remembered as tradition. Antiquarianism, in his hands, was a form of construction.