What they saw and heard and felt was certainly the word of proclamation, the sacraments of baptism and the Lord’s Supper the fellowship and gifts of the Spirit between brothers and sisters, but also the great “not yet,” the almost overwhelming difficulties and tasks arising from their witness to Jesus in the world, the convulsions of the Roman Empire moving to its climax and fall, the frailty of Christian flesh requiring constant exhortation and comfort and warning and punishment, much weakness and tribulation in which even the voice of the Spirit could only be a sigh and a stammering, a cry of yearning.
Yearning for what? This is where Christian hope comes in: not as a Deus ex machina or a piece of wishful thinking; but as a grasping of the promise which was the basis of the community and which stood firm in the face of all human weakness and tribulation. For the revelation of Easter was the origin of the community and therefore the beginning, actualised already and therefore past, of the full, conclusive, general revelation of the man Jesus, and therefore of His direct and comprehensive visibility for and to all those for whom as the Son of God He became man, the beginning of the visibility of their participation in His glory…
The Christian community has necessarily to be a gathering in this hope. The Christian has necessarily, then, to be the man who seizes this hope and lives in it. There is no other possibility either for the community or for the individual. The origin of both in the resurrection of Jesus makes it necessary that there should be not only faith in Him who was, and love for Him who is, but also hope in Him who comes.
Karl Barth, Church Dogmatics III/2, 488-489.