However, only one church design was operating in the New Testament. Despite adaptations, the church design remained basically the same. Let us use the bird analogy. Birds are designed with two wings, the function of which is to enable flying. That is their design.
Flight is their function.
The flight design does not change, but the flight function may be adapted. Birds such as eagles and hawks soar and glide. Quails and turkeys fly in short bursts of energy. Swallows and other smaller birds dart as they catch insects. Hummingbirds hover by beating their little wings at unbelievable speeds.