If a magician can become a priest, can a priest become a magician?

By accepting Josef Pharaoh turned ALL his magicians into Priests of Egypt.
When he no longer knew Josef, they became Magicians again. (like the snake and the staff)

Unfortunately the same logic applies to the priests of Israel.  When they become priests of the Baal.
By refusing the Tzaddik Isod Haolam, they become Magicians.