Final answer:
Jason released a dove to test the clashing rocks according to Greek mythology, specifically the tale of Jason and the Argonauts.
Step-by-step explanation:
Jason tested the clashing rocks by releasing a dove to fly through them. This event is taken from the Greek myth of Jason and the Argonauts. The Argonauts observed the dove to determine if it was safe for their ship to pass through. Fortunately, the dove managed to get through the rocks with just the loss of a few tail feathers, indicating that the Argonauts could proceed – a closely orchestrated timing that was crucial for their safe passage.