There are two kinds of critical mass. The first is theological. Critical mass occurs at any time/place where three people are present and Jesus is one of them. We all agree with that cerebrally, but viscerally—if we’re honest—we won’t feel good about those numbers unless we’re in a rural village of 18 in central China.
Practical critical mass is another animal. Twenty people in your living room is critical mass; 20 people in a high school gymnasium is not. So “practical” critical mass is the number of people relative to the size of the space they occupy.
The solution—if your facility allows—is to adjust the size and seating arrangement for your people on those “low” Sundays.
First, if the chairs are movable, take out 30 percent. Keep them nearby in the event that you need them. Increase the space between the chairs so that there is a 10-inch space (right to left) between the seating surfaces, and 30-36 inches between the rows. This will look goofy when the seats are empty, but when they are filled with people, a 30 percent smaller crowd will still fill your space and those present will have a “feel” of critical mass.
Last, when you’ve had one of those really bad days—attendance low, offering stunk, sermon sucked—ask yourself the question: “How many people did I deserve to preach to today?” Yep … the answer is always zero. If only one person shows up, you got grace.