Today, “fellowship” is a weird word. If you’ve been paying attention, you might’ve heard it in Hollywood: the Fellowship of the Ring. More often though, it’s a church word, even if it just Christian-speak for something else.
You might hear it in reference to some time at church, maybe between meetings, or perhaps on a Saturday evening, when Christians get together over snacks, coffee, a meal, a game, or a movie. Sometimes you hear some folk talking about their time hanging out with Christian friends at the golf course, saying “We had some good fellowship yesterday.” Once, a guy described to me his date from the previous night as “fellowship”. Scare quotes not intended.
It seems Christians call hanging out with unbelievers “being with friends”; if only Christians are involved it’s “fellowship”.
Some Christians, feeling that something is off, try to patch it up. Instead of a hangout time, they’ll set aside a special time. Since, they figure, koinonia (fellowship in Greek, if you care about original languages) means holding things in common with a spirit of unity then we need to grow to love each other—and that means liking one another. These special meetings will allow people to grow in knowledge and spiritual support of one another. See my rant about small groups.
The main mistakes in all of these ideas are that (A) they’re hopelessly bent inward and (B) they ignore the Biblical focus of fellowship.