The spirit world on earth is invisible to the average human being. Spirits, however, can see humans. Jozef Rulof was allowed to step out of his earthly body and, as a spirit, see everything on earth with his spiritual eyes. Together with his spiritual leader, he glided through houses and walls and saw people, but also many other spirits. He experienced that humans cannot see or feel him.
-They glided along, and passed through lots of houses and buildings. There was nothing to obstruct them and everything was visible to André. He saw people, many of whom radiated light. These he could clearly perceive. Around others he could see a grey haze, and he understood what this meant. They felt no love and lived an earthly life.
A View into the Hereafter p.270
-You’ll be able to perceive events on earth with your spiritual eyes, because you have been freed from your physical body, and you’ll be surprised to notice that everything appears just as you’re used to seeing it with your physical eyes. However, the light is different. The earth possesses a totally different light now. This isn’t the sunlight anymore, as that belongs to the material earth, where it’s seen through material eyes.
A View into the Hereafter p.153
-You notice, André, that nobody sees or feels us. Just try and give this servant a push; you’ll go right through him and he won’t notice anything. A very sensitive person would though, because he would be attuned to spiritual contact.
A View into the Hereafter p.155
Source: Quotations from the books of Jozef Rulof