Expositor's Bible Commentary Commentary Mark 5:20

"And he went his way, and began to publish in Decapolis how great things Jesus had done for him: and all men marvelled." — Mark 5:20 (ASV)

The man obeyed without argument and began to bear testimony of what “Jesus had done for him.” The Decapolis was a league of ten originally free Greek cities located (except Scythopolis) east of the Sea of Galilee and the Jordan River. These cities heard the testimony of the former demoniac and responded with amazement.