###Answer the question from the input provided. Please answer from input only.

###Input: Luther wrote "Aus tiefer Not schrei ich zu dir" ("From depths of woe I cry to you") in 1523 as a hymnic version of Psalm 130 and sent it as a sample to encourage evangelical colleagues to write psalm-hymns for use in German worship. In a collaboration with Paul Speratus, this and seven other hymns were published in the Achtliederbuch, the first Lutheran hymnal. In 1524 Luther developed his original four-stanza psalm paraphrase into a five-stanza Reformation hymn that developed the theme of "grace alone" more fully. Because it expressed essential Reformation doctrine, this expanded version of "Aus tiefer Not" was designated as a regular component of several regional Lutheran liturgies and was widely used at funerals, including Luther's own. Along with Erhart Hegenwalt's hymnic version of Psalm 51, Luther's expanded hymn was also adopted for use with the fifth part of Luther's catechism, concerning confession.

Luther wrote "Ach Gott, vom Himmel sieh darein" ("Oh God, look down from heaven"). "Nun komm, der Heiden Heiland" (Now come, Savior of the gentiles), based on Veni redemptor gentium, became the main hymn (Hauptlied) for Advent. He transformed A solus ortus cardine to "Christum wir sollen loben schon" ("We should now praise Christ") and Veni Creator Spiritus to "Komm, Gott Schöpfer, Heiliger Geist" ("Come, Holy Spirit, Lord God"). He wrote two hymns on the Ten Commandments, "Dies sind die heilgen Zehn Gebot" and "Mensch, willst du leben seliglich". His "Gelobet seist du, Jesu Christ" ("Praise be to You, Jesus Christ") became the main hymn for Christmas. He wrote for Pentecost "Nun bitten wir den Heiligen Geist", and adopted for Easter "Christ ist erstanden" (Christ is risen), based on Victimae paschali laudes. "Mit Fried und Freud ich fahr dahin", a paraphrase of Nunc dimittis, was intended for Purification, but became also a funeral hymn. He paraphrased the Te Deum as "Herr Gott, dich loben wir" with a simplified form of the melody. It became known as the German Te Deum.

Luther's 1541 hymn "Christ unser Herr zum Jordan kam" ("To Jordan came the Christ our Lord") reflects the structure and substance of his questions and answers concerning baptism in the Small Catechism. Luther adopted a preexisting Johann Walter tune associated with a hymnic setting of Psalm 67's prayer for grace; Wolf Heintz's four-part setting of the hymn was used to introduce the Lutheran Reformation in Halle in 1541. Preachers and composers of the 18th century, including J. S. Bach, used this rich hymn as a subject for their own work, although its objective baptismal theology was displaced by more subjective hymns under the influence of late-19th-century Lutheran pietism.

Luther's hymns were included in early Lutheran hymnals and spread the ideas of the Reformation. He supplied four of eight songs of the First Lutheran hymnal Achtliederbuch, 18 of 26 songs of the Erfurt Enchiridion, and 24 of the 32 songs in the first choral hymnal with settings by Johann Walter, Eyn geystlich Gesangk Buchleyn, all published in 1524.

Luther's hymns inspired composers to write music. Johann Sebastian Bach included several verses as chorales in his cantatas and based chorale cantatas entirely on them, namely Christ lag in Todes Banden, BWV 4, as early as possibly 1707, in his second annual cycle (1724 to 1725) Ach Gott, vom Himmel sieh darein, BWV 2, Christ unser Herr zum Jordan kam, BWV 7, Nun komm, der Heiden Heiland, BWV 62, Gelobet seist du, Jesu Christ, BWV 91, and Aus tiefer Not schrei ich zu dir, BWV 38, later Ein feste Burg ist unser Gott, BWV 80, and in 1735 Wär Gott nicht mit uns diese Zeit, BWV 14.



###Question: What does Luther's hymn Christ unser Herr zum jordan kam concern?

###Answer: {'answer':'baptism'}