d folio pages, averaging about
thirty-five titles to the page, of books and pamphlets written
either by or about him, that have been gathered into this single
collection, in a land foreign to the sphere of his labors, and
this list has been greatly augmented since 1894. Above all other
historical characters that have appeared since the first years of
Christianity, he is a man of the present day no less than of the
day in which he lived.

But Luther can be properly known and estimated only when he is
allowed to speak for himself. He should be seen not through the
eyes of others, but through our own. In order to judge the man
we must know all sides of the man, and read the heaviest as well
as the lightest of his works, the more scientific and theological
as well as the more practical and popular, his informal letters
as well as his formal treatises. We must take account of the time
of each writing and the circumstances under which it was
composed, of the adversaries against whom he was contending, and
of the progress which he made in his opinions as time went on.
The great fund of primary sources which the historical methods of
the last generation have made available should also be laid under
contribution to shed light upon his statements and his attitude
toward the various questions involved in his life-struggles.

As long as a writer can be read only in the language or languages
in which he wrote, this necessary closer contact with his
personality can be enjoyed only by a very limited circle of
advanced scholars. But many of these will be grateful for a
translation into their vernacular for more rapid reading, from
which they may turn to the standard text when a question of more
minute criticism is at stake. Even advanced students appreciate
accurately rendered and scholarly annotated translations, by
which the range of the leaders of human thought, with whom it is
possible for them to be occupied, may be greatly enlarged. Such
series of translations as those comprised in the well-edited
Ante-Nicene, Nicene and Post-Nicene Libraries of the Fathers have
served a most excellent purpose.

In the series introduced by this volume the attempt is made to
render a similar service with respect to Luther. This is no
ambitious project to reproduce in English all that he wrote or
that fell from his lips in the lecture-room or in the pulpit. The
plan has been to furnish within the space of ten volumes a
selection of such treat