Lutheran theologian Gerhard Forde (1927-2005) on the simultaneity--the at-the-same-time-ness--of gospel grace:
Generally law tends to remain the dominating reality and grace dwindles off into the status of a pious fiction. After all, we have to do something, don't we? . . . In the place of all such schemes, in the place of the conditional thinking that always traps us, we must put the absolute simultaneity of sin and righteousness. When God acts upon us with his grace, with his justifying deed, his pronouncement, we become simul justus et peccator, simultaneously righteous and sinner. . . . When the word of promise comes or begins to dawn on us, our reaction is 'I can't believe it! You mean that's all?' . . . Grace is the divine pronouncement itself, the morning star, the flash of lightning exploding in our darkness which reveals all truth simultaneously, the truth about God and the truth about us.
--Gerhard Forde, Justification by Faith: A Matter of Death and Life