Union with Christ is the believer's eternal state.
It has come to be understood increasingly, however, that with this "mystical" explanation of "in Christ" and "with Christ" one is on the wrong track. This is evident even from the fact that "being in Christ," "crucified, dead, raised, seated in heaven with him," obviously does not have the sense of a communion that becomes reality only in certain sublime moments, but rather of an abiding reality determinative for the whole of the Christian life, to which appeal can be made at all times, in all sorts of connections, and with respect to the whole church without distinction . . .
-- Herman Ridderbos, Paul: An Outline of His Theology