Sefer Chassidim 1136
G-d created man in His image. As long as man does not transgress and does not derive pleasure from gazing at immorality and does not try to make himself attractive to women and keeps his mind clear from immoral thoughts, then his image above in the heavenly spheres radiates. And as long as this image gleams, no demon is allowed to touch him. But when a person transgresses, his image above does not radiate, and angels of destruction attack him.[Note: This manifests itself in multiple forms of suffering that come upon a person].