A
In the early church - you can plainly see where the apostles raised up fellow brothers and sisters so that they then could go out and do the same. That is how the early church expanded. Granted the fellowships of believers were smaller and it was easier to know each brother and sister - to watch over their growth. Today's churches - some are so big that I can guarantee you that the pastor does not even know half (if that many) in his congregation. How can a pastor truly pastor his "flock" if it is so large without delegating responsibility to others that are raised up in the word?
How many of those does the Teaching Elder know? (In my denomination the Teaching Elder is the guy behind the pulpit. He's not the guy who ministers to the people, except through the sermons. That would be the Ruling Elders.) Maybe 100 by names and families? I'm not sure. (Never knew him well enogh to even ask him how his day was. lol)
I knew a Ruling Elder though. (He was a friend. I've been disabled for so long, I can't go to church anymore and can't participate, so we lost track over time.) I knew there were five, and among those five just about anyone who was interested was friends with one or more of them.
And then there are home parishes/churches. Big city, (Philly), so there are five -- one for each major section of the city. They meet once a month as a group. And in those home parishes, there are groups that meet at somebody's house once a week like any other home meeting. And out of the big church, there are several ministries so big, they have one or two full-time staff members, while they use as many who want to volunteer at whatever ministry there is. And out of those ministries they reach out into the community of people who need the help, which brings people to the Lord, and then often those people volunteer to help those ministries for a season or a lifetime.
The ministries include helping the poor and homeless (which my friend the Ruling Elder was in charge of), help people with different kinds of addictions, including sexual sin (which also fits in with feeding and assisting people with AIDs, HVC, and other diseases that attack the body because of the sin), and ministries for university campuses, including students, faculty and workers. Anyone who wants to help helps in an intimate way -- many ways.
So, yes, the Teaching Elder may not know the vast majority, but what's wrong with big churches? It doesn't mean you're stuck being one of the masses. You can still get to know people and join in anyway you feel led.