Here, Kathleen Norris (The Cloister Walk, p.127) summarizes a teaching by the 4th century monk Evagrius:
Anger is given to us by God to help us confront true evil. We err when we use it casually, against other people, to gratify our own desires for power or control.
I really like this idea that we sin when using something powerful in a “casual” manner. I think this works for all sorts of things. I’ll give it a shot.
Morphine is a powerful drug perfect for numbing the pain of a wounded man or putting someone to sleep during surgery. We err when we use it casually to relax and have a good time or temporarily forget our worries. That’s what beer is for. It’s weak and well-suited for casual use. Opiates are not.
The F-word is a potent curse or expression of outrage. We err when we use it casually after the pizza delivery guy is 5 minutes late.
Sexual intercourse is given to us by God to use our bodies to relate intimately with another person. We err when we use it casually to gratify ourselves, make money, or withold it to control others.
The sword (or machine gun) is a powerful weapon that we have been entrusted with for the defense of our families and the striking down of actual deadly foes. We err when we use it casually to take property we are envious of or aggressively control others.
Oaths are powerful words that bind our consciences up front so our resolve will not fail during the unseen trials later. We err when we use them casually as some sort of public display of honesty or intentions when our true loyalty lies elsewhere.
Smart phones are powerful tools capable of many things… and they are nearly always used casually to chat with friends, play video games, take fun pictures, brag subtly on social media sites, watch cat videos on YouTube, and listen to Taylor Swift (thankfully on headphones). We err when we… oh nevermind. I guess this doesn’t work for everything.
Update: My wife read this and put forth the idea that the theory doesn’t hold for the smart phone because it actually isn’t that powerful. I think she’s right. Despite all their sparkle and utility, they are terribly overrated in their ability to affect substantial sociological or interpersonal change.