The fact remains that there are evil spirits in the world. In fact some assertion claims that they are quite much more than the population of people on earth. We should not be ignorant of this. We should live our lives in full awareness of the fact that the enemy (which is the devil) is walking about like a roaring lion seeking for whom he might devour. Never allow yourself to be the one whom the evil one will devour. The Bible says that those who are God's keep themselves so that the evil one will not harm them. They are not such as live their lives recklessly. They are not those who play with sin. Anyone who plays around with sin is actually offering his or her self as a cheap prey for the devil.
When we are asking whether demons are capable of touching people physically, we must not forget that we are living in a world where evil in very predominant. The much evil that we are experiencing in the world is caused by evil spirits. These evil spirits have entered into the hearts of men and make them to manufacture all kinds of wickedness. There would not have been evil in this world had it been that the evil spirits did not invade this world. From the very moment that Adam disobeyed God in the garden of Eden and ate the forbidden fruit, Satan had taken sway and brought much evil upon us in the world.
What does the Bible says? It says that he that is born of God keeps himself and the evil one does not touch him. He that belongs to God must keep himself in the word of God. He must refrain from everything that is evil. Let us be obedient to God because it is the children of disobedience that suffers from the wicked forces.