8 Will your Majesties listen to other actions of this same Prince, which you may more worthily imitate? He diminished none of the privileges of the sacred virgins, he filled the priestly offices with nobles, he did not refuse the cost of the Roman ceremonies, and following the rejoicing Senate through all the streets of the eternal city, he contentedly beheld the shrines with unmoved countenance, he read the names of the gods inscribed on the pediments, he enquired about the origin of the temples, and expressed admiration for their builders.
Although he himself followed another religion, he maintained its own for the empire, for everyone has his own customs, everyone his own rites. The divine Mind has distributed different guardians and different cults to different cities. As souls are separately given to infants as they are born, so to peoples the genius of their destiny. Here comes in the proof from advantage, which most of all vouches to man for the gods. For, since our reason is wholly clouded, whence does the knowledge of the gods more rightly come to us, than from the memory and evidence of prosperity? Now if a long period gives authority to religious customs, we ought to keep faith with so many centuries, and to follow our ancestors, as they happily followed theirs.
Source: Memorial of Symmachus (New Advent)