An Etymological Dictionary of the German Language/Annotated/Papst
Papst, Pabst, masculine, ‘pope,’ from Middle High German bâbes, and with an excrescent t (see Obst and Palast), bâbest; Old High German bâbes first occurs about 1000 A.D. (in Notker); from the equivalent Latin pâpa. The initial and medial b in Old High German and Middle High German in contrast to Latin p may be compared with bëch, balme, bapel, and their variants pëch, palme, papel, in Middle High German The s of the Old High German form bâbes (earlier *bâbas?) is both strange and difficult to explain; compare Old Slovenian papežĭ, borrowed from it. This Latin Church word, which passed into German at a late period, cannot be connected with Modern Greek πάππας (compare Pfaffe); most of the corresponding Romance words have, however, no s (Italian papa, French pape). Yet Old French has sometimes pape-s instead of pape, with an inorganic s in the nominative (compare Pfau), for in Old French numerous mascs. in a could take an s in the nominative (poetes from poeta, prophetes from propheta, hermites from eremita, homicides from homicida, &c.). In Middle European German this form in s afterwards constituted the stem; besides Old High German bâbes compare also Dutch paus (from Old Low German and Old Dutch pavos, recorded even in the 9th century). The Low German form seems to have passed in the 10th century to the south of Germany. Old Icelandic páfe was probably formed under the influence of Anglo-Saxon pâpa (Latin pâpa), English pope. Moreover, Middle Latin pâpa was a respectful term used in addressing bishops, and since Leo the Great a title of the Roman pope, and also since Hierocles the title of the patriarch of Alexandria. Gregory VII. decreed in 1075 the exclusive right of the Roman pontifex to the title papa. The fact that Anglo-Saxon has preserved the Latin word in a purer form is explained by its having been borrowed at an earlier period.