Torah Hieroglyphics

The Sefer HaBris (2:12:5) explains that the Sages had many different styles which they utilized in expressing Aggadic concepts. In total he lists fifteen.
The first one he terms "Hieroglyphics." He explains that this is an ancient method utilized both by Torah scholars as well as others as a means to convey a message to others, while keeping the message hidden from another group of people. They would convey the message by means of an illustration whose symbolism would only be understood by a select few. By way of example he shows how the Roman Empreror Antoninus asked Rabbi Yehudah HaNasi how he can ensure that his son Asoyurus would be his successor and also free the city of Tiberius from paying taxes. By way of answer Rabbi Yehudah HaNasi placed one man on the shoulders of another and gave the one on top a dove. He then told the man on bottom to tell the person riding on his shoulders to free the bird. Antoninus understood what Rebbe Yehudah was telling him.

The Sefer HaBris explains that one advantage of this methodology is that as no words are spoken, it prevents spies from hearing what you don't wish for them to hear. He further say that the illustration can be in the form of a pantomime as described above, or a picture drawn on a table or wall. If the intended recipient is at a distance, then drawing a picture and mailing it would be another alternative. If others would read the letter they would not grasp the significance of the picture. The intended recipient will understand. And if the person lacks drawing skills, he can simply write a description of what it is he wishes to depict.
In the Talmud, which was intended to send a message to later generations, the most reliable manner was to write descriptions of things for later generations to decode the intent. They wrote stories of things that never happened as they didn't care about the story that they were describing, or if the objects they described even exist. They described oxen with wings, two-headed eagles, and horned roosters all the while only caring about the message. This is the way to understand the stories about Rabbah bar bar Chana and the amazing beasts he saw in the sea. Here is something from one of my blogs:

Sefer HaBris (1:2:7) discusses statements of our Sages with regards to the sun, moon and stars and their paths through the heavens. He says that the statements of the Sages are not meant to be taken at their literal word. The reality is that they are comments that don't seem to make sense, as they were never meant to be taken literally. The same is true of all statements in the Talmud and Midrash which do not seem to make sense or are contradicted by our experience. We should understand that the Sages never meant them literally, but as an allusion to some wisdom or as a riddle or allegory. The authors of these statements themselves were well aware that the simple meaning of their words went against reality. They didn't care because they were focused on their intended message which was full of great wisdom which was true.

When our Sages write that a gnat entered the brain of Titus and after his death was found to be the size of a year old bird, weighing two pounds, with a copper mouth and iron claws they knew that a bird of this size could not possibly fit into the head of a person. They also knew that there was no reason for God to make such a miracle. If God wanted to bring pain to Titus He could have accomplished that without such a miracle. And why was its mouth of copper and its claws of iron? Why not the opposite?

Really they were teaching a lesson with regards to the ultimate downfall of Rome. Who will bring about the downfall and how. They intentionally hid their meaning from the masses as they knew that the other Sages would understand their intent and ignore the metaphor.

Ramchal , in Maamar al HaAggadoth, makes the same point. CL