It is said that God allows the demons to attack us for five reasons. The first is that, through being attacked and fighting back, we should learn to distinguish virtue from sin. The second is that having acquired virtue by struggle and labor we should keep it firm and unalterable. The third, that progressing in virtue we should not think highly of ourselves but learn humility. The fourth, that having experienced in practice the wickedness of sin we should hate it with perfect hatred. Finally, the fifth and most important is that having been freed from the passions we should not forget our weakness and the strength of Him that helped us.
Contributed by: boyznamedsue