Reval, Fleming found that Elsabe had married another man and became engaged to her sister, Anna Niehus. In 1639 Fleming resumed his medical studies at the University of Leiden, and in 1640 was awarded a doctorate. He settled in Hamburg, where he died on 2 April 1640. Poetry With his contemporaries Martin Opitz (1597–1639), Andreas Gryphius (1616–1664), Christian Hoffmann von Hoffmannswaldau (1616–1679) and the rather later Daniel Casper von Lohenstein (1635–1683), Fleming is one of the writers now called "the Silesian poets" or "the Silesian school". As a lyricist he stands in the front rank of German poets. Fleming's well-known poems include (On the Death of a Child) and Madrigal. A number of his sonnets are about the places he visited in his travels. The only collections published in his lifetime were Rubella seu Suaviorum Liber (1631) and Klagegedichte über das unschuldigste Leiden und Tod unsers Erlösers Jesu Christi (Laments concerning the most innocent Suffering and Death of our Saviour Jesus Christ), printed early in 1632, the second of which begins with an invocation of Melpomene, the Muse of tragedy. His (Poems in German), published posthumously in 1642, was later renamed (Spiritual and Secular Poems) and contains many notable love-songs. Fleming wrote in Latin as well as in German, and his Latin poems were published in a single volume in 1863, edited by Johann Martin Lappenberg. Fleming has been called a man of "real poetic genius", "the only good poet in Germany during the Thirty Years' War", "possibly the greatest German lyric poet of the seventeenth century" and "the German Herrick". Günter Grass has called him "one of the major figures in German seventeenth-century literature". Musical settings Fleming wrote the hymn in nine stanzas "" (In all that I do) on the melody of "" by Heinrich Isaac, which is contained in several hymnals. Johann Sebastian Bach used the final stanza to close both cantatas (BWV 13) and Sie werden euch in den Bann tun (BWV 44). The complete hymn is the base for Bach's chorale cantata (BWV 97). Already in the 17th century another composer, David Pohle (1624–1695), had set twelve of Fleming's love-songs to music. Johannes Brahms set "Lass dich nur nichts bedauern" as Geistliches Lied, Op. 30. Works Rubella seu Suaviorum Liber (1631) Klagegedichte über das unschüldigste Leiden undt Tod unsers Erlösers Jesu Christi (Laments concerning the most innocent Suffering and Death of our Saviour Jesus Christ)