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The Apology is Melanchthon’s not Luther’s.

The Apology stopped being Melanchthon's when he "matured to the point" of not agreeing with his own confession. Luther wrote in 1532, "the Augsburg Confession is mine." The Unaltered Augsburg Confession and its Apology are the property of those who confess them.

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Am I to assume from this that the history of what one believes has no bearing on his final beliefs? Are we then being familiar with Speratus’ work to consign everything he has written to the rubbish pile, except his final confession?

Is that not the meaning of "Always Reforming"? Even Calvin signed the Augsburg Confession before he "matured to the point" of consigning its doctrine to the rubbish pile.