Social Media has been a mixed blessing to our little religious world. The positives, as I see them, are as follows: you get to know people better, there is more visibility for ministries, and people can connect more easily. I think it also helps regulate behavior. For anyone who has read letters from the early part of our movement, it is easily apparent that many of our venerable forefathers must have spent a great deal of time typing excommunications. However, with social media there is a degree of peer pressure that helps regulate some insane behavior. Some.
However, there is also a great deal of negative. One issue is that people can get to know each other better. Familiarity, as we know, does breed contempt. And the more we know about people and their intimate religious and political beliefs the more we tend to dislike each other. And social media seems to be the one place where people feel able to post their innermost secrets and beliefs on all sorts of topics. In that same vein, it puts all sorts of people into contact. In one sense, it's good that people are getting connected. However, the down side is that it makes people more connected. People can easily manipulate their image so that they seem great because it appears they are religiously active, or they take pretty pictures, or they are half way around the world and that's appealing. But social media is also a great way for people to put their "best foot forward" and disguise themselves and their true intentions.
Another issue is that some bishops think it's appropriate to share decrees and other proclamations on things like Facebook. Granted, it's okay to publicize information in this way. But posting a Facebook post that you're incardinating someone isn't the way to do it. Imagine if a business' HR consisted of their saying "Congratulations Joe Smith! You're hired!" If you shouldn't run a McDonald's like that, then it's not acceptable for a church.
There is also an issue with social media and parishioners. In general, I follow the practice that one should be very judicious about their social media account if they are a cleric. Political postings that can alienate the faithful should be avoided. I prefer to think that clergy project a "tabula rasa" as much as possible. We are called to minister to a wide audience of people. Sure, we have our own beliefs, thoughts, feelings, passions, etc. But we live in a divided, fallen world. It is so divided that it doesn't help if we are further dividing it. We let people come to us and administer, as much as we can, the salve of forgiveness and mercy. To whomever should have need.
"You are priests, not social or political leaders. Let us not be under the illusion that we are serving the Gospel through an exaggerated interest in the wide field of temporal problems." - Pope St. John Paul the Great