In Luke 8, Jesus confronts the demoniac known as Legion. And in a spectacular demonstration of His power, and with something of a sense of irony, Jesus sends the demons into a herd of pigs, who then rush over a cliff to a watery grave.
Yet in this story, some basic realities about demons are revealed:
Demons are numerous. From the very name of the demoniac, “Legion,” it is evident that this man was inhabited by a large host of demons, since Legion was a term used to indicate a group of 6000 Roman soldiers. Revelation 12:1-9 indicates that as many as one-third of all the angels in heaven may have fallen with Satan in his evil rebellion against God.
Demons support the evil work of Satan (e.g., Mt. 12:26-28, 43-45; Rev. 12:7) and are enemies of both God and man. While these many demons inhabited this man, they did not benefit the man, but were in the process of destroying him. He was naked and homeless (v. 27), was violent towards others (Mt. 8:28) and himself (Mk. 5:5), and unable to control his own mind and words (Lk. 8:28; Mk. 5:5). Satan and his followers can do nothing beneficial or constructive but only seek to devour and destroy (1 Pt. 5:8).
Further, demons oppose God, His angels, and His people (e.g., Eph. 6:12; Dan. 10:13). As they said to Christ in this account, “what business do we have with each other, Jesus…?” They have nothing to do with each other. They are fundamentally and fully in opposition to each other. They know of Christ and they know of truth (e.g., Js. 2:19), but they are incapable of being transformed, and always stand opposed to Christ and the truth, just like their leader.
Demons are capable of indwelling bodies — both human and animal — as this story reveals. However, that does not mean that every sinful activity of an unbeliever is due to demonic indwelling; the lust of the flesh is sufficient to produce much sin (Js. 1:14-16). Nor does it mean that demons only have power to influence people when they indwell individuals; they also have ability and power to influence the world system and influence the thinking of people in that way (e.g., 1 Jn. 2:15-17).
Demons influence the minds of those they indwell (e.g., 2 Cor. 4:4; 1 Tim. 4:1; Js. 3:15). Just as these demons controlled the mind of this pitiful man, so that is their ultimate aim in the world, to control and manipulate those they indwell and those they influence. This “mind work” is also obviously designed to lead men astray from the truth (2 Cor. 4:4).
Demons have significant (supernatural) and physical power, as evidenced by the fact that there were no shackles able to restrain this man (v. 29). The power was not inherent to the man himself, but that strength was resident in the demons.
We also know from other passages that demons also deceive nations (Rev. 16:14). Through miraculous signs they will deceive the nations at the end of the age to gather them for war against Christ.
Yet for all these truths about them, the believer need not fear the demons. As Christ demonstrated in this miracle, He is sovereign over them, and they have no choice but to submit to them. For all their power, their power is limited and finite. Christ’s power is unlimited and infinite. Perhaps it was a miracle like this one that was in John’s mind when he reminded the readers of his first epistle that, “Greater is He who is in you than he who is in the world” (1 Jn. 4:4).