Mark 5:13

And he gave them leave (kai epetrepsen autoi). These words present the crucial difficulty for interpreters as to why Jesus allowed the demons to enter the hogs and destroy them instead of sending them back to the abyss. Certainly it was better for hogs to perish than men, but this loss of property raises a difficulty of its own akin to the problem of tornadoes and earthquakes. The question of one man containing so many demons is difficult also, but not much more so than how one demon can dwell in a man and make his home there. One is reminded of the man out of whom a demon was cast, but the demon came back with seven other demons and took possession. Gould thinks that this man with a legion of demons merely makes a historical exaggeration. "I feel as if I were possessed by a thousand devils." That is too easy an explanation. See on "Mt 8:32" for "rushed down the steep." They were choked (epnigonto). Imperfect tense picturing graphically the disappearance of pig after pig in the sea. Luke 8:33 has apegnigh, choked off, constative second aorist passive indicative, treated as a whole, Matthew 8:32 merely has "perished" (apeqanon; died).