How serious a sin is watching porn?

Number one is Christ says in the gospel that our eye is basically the window to our soul, and whatever we let in defines the whole inner state of the person. And he talks about if a person's eye becomes dark, the whole person becomes dark. This material is the primary way in which the devil has enslaved almost the entire world. What also do the saints say? The saints say if we watch someone else sin and condone it, we participate in it. So for those who are Christians who participate in this, St. Paul makes it very clear the sexually immoral will not be saved. We have this from the writings of the saints as well. When people participate in this illicit material, they are participating in the sins of what they are watching, and it is staining and darkening their own soul and their own heart. It is very serious and very grievous, and it must be treated with the most absolute diligence and hard work to free us and to make sure that our souls are pure from this evil, this evil stench of the devil.