GERSON, Johannes (1363-1429). De custodia linguae et corde bene ruminanda. [Cologne: Ulrich Zel, about 1470.]

Second edition of a tract on the morality of speaking ill of others behind their backs, from the first printer at Cologne. Zel was the primary printer of tracts by Jean Gerson, the French reformer and scholar who defended Joan of Arc and was an early thinker on natural rights theory. "This brief tract considering the moral implications of speaking ill of others in their absence is typical of Gerson's theological explication. His starting point is a simple question bearing on everyday life, and he brings in scripture and teachings of the Church Fathers (here, Augustine) to guide the discussion. He leads the reader to examine their motivation and consequences and ultimately advises the reader to consider it with the 'eye of the heart.' This internal examination to deal with a social question reveals the foundation of Gerson's thought and his optimistic belief in the good of mankind when directed properly" (BPH). ISTC records only 2 copies in the US. Goff G-219; H 7683*; BMC I 184; BSB-Ink G-191; GW 10755. See Ford, BPH 96 (first edition, also from Zel).

Chancery quarto (192 x 126mm). 6 leaves. Initials spaces filled in red, rubricated in red and silver. 18th-century paste paper wrappers, stab sewn (renewed with buckram at fold, remains of spine label). Provenance: a few manicules (some trimmed) – Darmstadt, Palace Library of the Grand Duke of Hesse (Grossherzoglich-Hessische Hofbibliothek stamp on first leaf).