Martin Luther wrote his great hymn ‘Ein feste Burg ist unser Gott’ (‘A mighty fortress is our God’) towards the end of the 1520s, marrying words and music with a surefooted sense of gravity, religious fervour and the ability to touch hearts with its directness and simplicity. The melody mostly moves in steps and shies away from extremes (both high and low): it’s a good sing, easy to remember and stirs the spirit. It speaks of unshakeable faith, too, and it soon entered the German consciousness and started its own musical journey. The Choir of Clare College, Cambridge gives a rousing rendition on its recent Reformation programme, followed immediately by JS Bach’s Cantata No 80, a glorious creation that uses the great hymn as its chorale (which, in turn, was written for Reformation Day, October 31, 1724). Mendelssohn’s Reformation Symphony, written in 1830 to mark 500 years since the Presentation of the Augsburg Confession, employs Luther’s theme in the fourth movement (the music switching from 4/4 to 2/4 to accommodate the hymn’s metre). In a fine performance, like this recent one in John Eliot Gardiner’s series for LSO Live, the way in which the chorale grows from its solo-flute introduction, adding in wind and brass as it goes, to its stately apotheosis for full orchestra is magnificent. Meyerbeer’s 1836 opera Les Huguenots culminates, in its blood-stained closing pages, with the St Bartholomew’s Day Massacre, in 1572, in which thousands of (Protestant) Huguenots were murdered by the Catholics. To set the scene, Meyebeer used Luther’s chorale in the brief Prelude with which he replaced the longer overture he’d originally intended. Meanwhile, Wagner’s seldom-heard, and outrageously bombastic, Kaisermarsch (‘Emperor’s March’) uses ‘Ein feste Burg’ to symbolise the victorious German troops who had recently defeated the French. Whereas Alexander Glazunov’s Finnish Fantasy, Op 88(1909)– altogether more luminous in sound and spectacularly orchestrated (as well you might expect from this composer) – uses Luther’s chorale to illustrate a national spirit.