Christus is the title given by the composer's brother Paul to fragments of an unfinished oratorio by Felix Mendelssohn, published posthumously as Op. 97. The work was suggested by Christian Karl Josias von Bunsen, who compiled the German libretto from biblical sources. Composition began in 1846 and continued through Mendelssohn's last year. The completed portions include a tenor recitative relating Christ's birth, a TBB chorus "Where is the newborn", the well known SATB chorus "There Shall a Star from Jacob Shine Forth" using Philipp Nicolai's chorale "Wie schön leuchtet der Morgenstern", and a passion section ending with another chorale, Paul Gerhardt's "O Welt, sieh hier dein Leben". The first performance took place in 1852.
Jeffrey S. Sposato's 2006 The Price of Assimilation: Felix Mendelssohn and the Nineteenth-Century Anti-Semitic Tradition discusses both Christus and Mendelssohn's cuts in the Matthäuspassion and discerns an agenda to promote "the Lutheran concept of universal guilt for Christ's death" over the prevailing antisemitism of the time.
- Todd, R. Larry. Mendelssohn: a Life in Music (2003) pp. 554-6
- Sposato, Jeffrey S.,, The Price of Assimilation, November 2005 , pp. 163-177(15), Oxford Scholarship Online Monographs (abstract)