Ich glaube, lieber Herr, hilf meinem Unglauben, BWV 109
... that Bach assigned two opposing voices to one singer in his cantata Ich glaube, lieber Herr, hilf meinem Unglauben, BWV 109, for the 21st Sunday after Trinity?
... that Bach assigned two opposing voices to one singer in his <a href="./Bach_cantata" id="mwB4k" rel="mw:WikiLink" title="Bach cantata">cantata</a> <i id="mwB4o"><b id="mwB4s"><a href="./Ich_glaube,_lieber_Herr,_hilf_meinem_Unglauben,_BWV_109" id="mwB4w" rel="mw:WikiLink" title="Ich glaube, lieber Herr, hilf meinem Unglauben, BWV 109">Ich glaube, lieber Herr, hilf meinem Unglauben, BWV 109</a></b></i>, for the <a class="mw-redirect" href="./List_of_Bach_cantatas_by_liturgical_function#Trinity_XXI" id="mwB40" rel="mw:WikiLink" title="List of Bach cantatas by liturgical function">21st Sunday after Trinity</a>?