‘To be a Christian is per definitionem to be in Christ. The place of the community as such, the theatre of their history, the ground on which they stand, the air that they breathe, and therefore the standard of what they do and do not do, is indicated by this expression. Being in Christ is the a priori of all the instruction that Paul gives his churches, all the comfort and exhortation he addresses to them. – Karl Barth, Church Dogmatics IV/2, p. 277.