Zararthustra, Zoroaster, by most accounts was member of a more nomadic clan. His name means something like, "He who manages Camels." Nor did he appear out of nowhere, he belonged to a tradition of Idea that predated his time upon earth by many, many generations. The Idea when he was born had a professional class, a body of understandings and a priesthood, and when Zoroaster was around seven years old he started his training to become a priest. While a person is born with many attributes, capacities that enable them to get a toe hold on the world they are born into, no one is born with a body of knowledge that builds through the course of passing through the world. Choosing to become a priest suggests an interest in something other than managing Camels, and oddly Zoroaster's name has been translated as "with angry/furious Camels" "who is fostering/cherishing camels" "desiring Camels" and "with yellow Camels." Then in his thirties Zoroaster had a vision, he saw a shining being which introduced himself as "Good Purpose" and "Good Purpose" taught Zoroaster about what is was to be a "Wise Spirit." As the vision continued Zoroaster began to sense the presence of another more primal spirit which seems to have two parts, one part hostile and lying called Druj, the other part true and honest called Asha. The experience was a Revelation which persuaded Zoroaster to spend the remainder of his days devoted to Asha.
It's also the case that visions can be very confusing and describing them not always easy. Too accurate a description might make very little sense to a listener, so there's a certain interpretation that occurs. At the same time back in those days there was a drink that people concerned with higher callings reckoned was a big assistance in the whole process of visions. It was an infusion of herbs, spices and probably honey. There's a vague suggestion by more recent researchers that one of the ingredients was a Mushroom that grew on Cow manure, but the point is that revelation is an act of revealing or disclosing, it's usually dramatic and includes the idea of realizing something previously not known. And of course revelation is sometimes thought of as a manifestation of the divine will or truth. As well it's probably wrong to assume that just because you're high on Mushrooms therefore God must be talking to you. But suddenly realizing something, sorting it out, making that nagging something comprehendible in your mind, doesn't necessarily require God or Mushrooms. In many ways how you explain your revelation to others is somewhat central to "Good Purpose." You can't just say, this ring was made for Henry III, it's all gold and 20 carat diamonds, and you can have it for two million dollars, without some sort of provenance. And if you want to know why you might not be able to sell Henry III's ring without some sort of provenance, well you can call it a Druj and Asha kind of thing.