The church I grew up in has doubled in size since my time there in the 80s and 90s. I'm not great at estimating numbers, but I would say there were 500-750 members fifteen years ago, and maybe 1000-1500 today? They just launched a second campus by adopting and revitalizing a struggling congregation in another area of town, and are really thriving, changing lives and the community.
When I visit my home congregation now, it bears very little physical resemblance to the church I loved in my youth. It has a new building in a new location, and a new pastor as well. I still see our old family friends, but I also see many, many people I don't know. A good friend with whom I grew up at this church is still active there, with her parents and now her husband and son, and even she says that there are many, many people that she doesn't know.
But, you know, it's okay that we don't know everyone or recognize every face. Sure, it was nice knowing most people--the more active members, anyway--as I was growing up there. But knowing everybody is not what church is about. The church is not there to serve its own members or to perpetuate itself as a social club. Fellowship meals and small groups are nice, and serve a valuable purpose, but if such gatherings are ends unto themselves, then we have very much missed the point. We are called to serve, to reach out, to include.
There is a great article by John Flowers and Karen Vannoy called "Incentives to Decline." It explains why some churches, even if they say they want to grow, really would prefer to stay the same, because growth would mean sacrificing some comfort, some intimacy, even some power. Bringing more people into the fold would mean they might not get as much say in decision-making. They might not like some of the physical and organizational changes that growth requires. They might not recognize every face or know every person by name.
Sure, it's a little uncomfortable to return to my home church and not feel quite as "at home" as I might if I knew every person's name or knew where every room was located, or if I could return to the exact places where special memories were made. But that feeling pales in comparison to the excitement of seeing this congregation that is so close to my heart grow and thrive and make a huge difference for the kingdom of God.