Sefer Chasidim ספר חסידים

The Sefer Chasidim is neither a code nor a treatise but a collection of cases: a man promised and could not keep it; a neighbour makes noise; a copyist spoiled a book; a rich man gives much, but for show. To each case it says how to act—and often more strictly than the law requires. The cases number, according to the edition, between twelve hundred and nineteen hundred.

It is the chief monument of the Chasidei Ashkenaz, the movement of the Rhineland communities of the twelfth and thirteenth centuries, for whom the measure was not the law but "din shamayim", the judgement of heaven. From it come many customs still kept today and having no other source: how to treat old books, what not to do in a cemetery, how not to shame the poor.