Always, night and day, he was in the mountains and in the tombs, crying out and cutting himself with stones, Matt 5:5.
The mad man illustrates of all who are in captivity to Satan. Right up to the present it has been the aim of the great seducer to make man ruin himself through sin. And how many people do things under the influence of sin that is as unreasonable as the man’s activity reported above.
The end is God’s judgement, for sin is an affront to him who is holy and just. Nevertheless, in all the suffering and misery of sin there is salvation only by accepting Jesus as Lord, master and Saviour. TSG 04-04-09.