When NASA was first planning a trip to the moon, it had to reinvent the whole idea of a spacecraft. The moon's gravity is a quarter that of earth and therefore everything weighed a lot less. Weight however was of great importance to the spacecraft as it took three pounds of fuel to get one pound of spaceship on to the moon's surface. The skin of the craft was therefore made of aluminum similar to kitchen foil and the pilot stood rather than sat on a seat in order to save weight. The spacecraft to take a human down to the moon's surface and off again was a completely new invention and entirely different from any other craft in the earth's atmosphere.
The Household of Faith method of evangelism proposes to invent Christian ministry afresh, though in another sense it is not new at all. The Early Church in the first three centuries of her existence had nothing but households to use for evangelism. They were however very successful in their communities through ordinary houses. It was not at all like our Christian church today which has become institutionalized and which will need to invent Christian ministry all over again even to survive.