Expositor's Bible Commentary Commentary Mark 5:12

"And they besought him, saying, Send us into the swine, that we may enter into them." — Mark 5:12 (ASV)

What caused the stampede of the pigs was the entrance of the demons into them. They were bent on destruction. Not having been able to destroy the man, they destroyed the pigs. Demons are emissaries of Satan, the Destroyer. Why the sovereign Lord allowed this destruction is uncertain, but perhaps he wanted to give tangible evidence to the man and to the people that the demons had actually left him.