Those who wish to hear about the Gods should have been well ...

Those who wish to hear about the Gods should have been well guided from childhood, and not habituated to foolish beliefs. They should also be in disposition good and sensible, that they may properly attend to the teaching.
They ought also to know the common conceptions. Common conceptions are those to which all men agree as soon as they are asked; for instance, that all god [here and elsewhere, = godhood, divine nature] is good, free from passion, free from change. For whatever suffers change does so for the worse or the better; if for the worse, it is made bad; if for the better, it must have been bad at first.

Sallustius

I. What the disciple should be; and concerning Common Conceptions, as translated by Gilbert Murray - On the Gods and the Cosmos