You don't have to spend much time with souls these days to realize that the internet is an occasion of sin for a lot of people. I've been trying to figure out why this should be, and why the attachment to sins facilitated by the internet become so binding so quickly.
My proposal for how to think about it has to do with the indulgent spoiling of the curiosity of the mind and the eyes. When using or surfing the web, you can get an immediate answer--though not necessarily the best or correct one--to anything you might have a casual or passing thought about. The same goes for images. As soon as some useless or passing curiosity comes into my thoughts, (e.g. How big is the sun? Why is White Castle so good? What did Zooey Deschanel wear to the Screen Actors Guild Awards?) all I have to do is type it into the search box and in a third of a second or so (according to Google anyway) I have what I want.
This process trains the mind and eyes to get what they want immediately, without reflection or effort. So, having made a spoiled child out of the curiosity of the mind and eyes, one has little defense when curiosities emerge that are objectively sinful, hurtful or degrading to oneself or others, or against one's state in life.
In order that I might have something to say to people thus afflicted, as well as a practice for myself, I have come up with a spiritual practice for the struggle against this occasion of sin. It's based on what John of the Cross calls the "active night of sense" in The Ascent of Mount Carmel. John recommends that in order to make a beginning of the spiritual life, we need to deny our outward senses what delights them, thus leaving them 'in the dark.'* My adaption of this for the use of the internet goes like this:
Look for opportunities to enter the "active night of sense" in the use of the internet. Before typing in that search term or clicking that link, examine yourself. Do I need to know this information? Is there a genuine spiritual or charitable concern the leads to my curiosity? If not, take the opportunity to leave the curiosity in the dark. By this practice we can unspoil our curiosity and become better equipped to deal with the more serious temptation to sin that the web affords.
*This is the first step of John's fourfold scheme for the spiritual ascent. After the active night of sense comes the passive, followed by the active and passive nights of spirit.