Estranged father of Tommy Levinson, a member of Seth's cult. Jason was aware his son had been brainwashed into joining the cult, located inside a highly fortified compound north of Seattle. Jason had been camped near Seth's property, hoping to see some sign of his son who had been in the company of the leader for nine months. He hired someone to go in and retrieve him, but he returned with a bullet in the leg.
Jason believed SG-1 and Jacob Carter to be de-programmers, and was eager to join them in infiltrating the encampment. When SG-1 completed its mission (including the rescue of Jason and other cult members), all the members of Seth's cult were zapped with a zat'ni'katel discharge, wiping their memories of ever being captured.
After their escape, Jason was reunited with his son.
Seth - Jason Levinson is eager to take matters into his own hands in retrieving his son but is stopped by O'Neill and the other "de-programmers."