How to create a strong halo light effect? How to achieve the strong light effect (you may see in some games and 3d renders), where the light is so strong it's penetrating the objects?
Use the compositor Glare node with the type set to 'Fog Glow'.

Ensure you have a suitable emission material behind the 'windows' to ensure there is a bright area for the glow to act on. Add a 'Glow' node and set the type to 'Fog Glow'.

Adjust the parameters of the Fog Glow and/or change the intensity of the emitter to get the desired effect. 



No glow, a moderate glow, a strong glow :