Formed by the Spirit
The twelve apostles that our Lord gathered to himself were very individualistic. They were very much like the hydrogen and phosphate and sulphur in a laboratory. In fact, we have in the laboratory all the chemicals that enter into the constitution of a baby. Why can we not make a baby? Because we lack that vivifying, unifying power which is a soul. So the apostles, disparate, disconnected, disjointed, could not form this body of Christ. They could be formed only by Christ and his Spirit in them. And as through the physical body of our Lord, it was God who taught, it was God who covered, it was God who sanctified.