New Defender's Study Bible Notes
5:9 Legion. A Roman legion could contain as many as six thousand soldiers, but the implication here is simply “many.” Actually, there were at least two thousand (Mark 5:13). Jesus had asked the man his name, but the dominant evil spirit answered, using the man’s vocal apparatus. The same phenomenon is occasionally encountered in demon-possessed people today, with the responding spirit exhibiting knowledge and voice structure markedly different from that of the person possessed.