Where is the river Styx, and who rows the boat across it?
The River Styx winds around Hades (Hell) and Charon is the boatman who ferries the dead across the river and into the Underworld.
The River Styx is a metaphor for death: there is no way back here from death save only that The Eternal sends you back to finish your penance. That leads to salvation, and admittance to the Palace of the Eternal.
Beware the errors of Thetis, mother of Achilles.
Thetis brought her newborn son Achilles to the River Styx hoping to make him immortal. She dipped him into the water that brought instant death and immortality in the bargain. To touch this water was death and immortality. She also touched the water.
Thetis lost her spirit as did Achilles. Such is the price for meddling with mortality. Achilles became a warrior and was seemingly invincible, many honorable men died on his sword and he was unmoved by his invincibility. Achilles was killed by a poison arrow in his heel, the only place the Styx water did not touch.
Thetis and Achilles both were brought before Zeus. "As you are immortal, you cannot die. As you tried to cheat death, you are not numbered among the honored dead. Thetis is condemned to pour out Styx water so that all might remember her folly. Achilles is innocent of his mother's misdoing. He is pardoned."
Thetis, now called Aquarius, resides in the February sky, in the coldest time of year, the time of want, ruthlessness, and starvation, bared with all her faults and calling out for others not to make her mistakes. She pours poison tears by the bucketful, and there is no end to her tears. Her only solace is that we might learn from her mistake."
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