Ach Gott, vom Himmel sieh darein (Oh God, look down from heaven), BWV 2 is a chorale cantata composed by Johann Sebastian Bach for the second Sunday after Trinity in 1724. First performed on 18 June in Leipzig, it is the second cantata of his chorale cantata cycle. The church cantata is based on Martin Luther's 1524 hymn "Ach Gott, vom Himmel sieh darein", a paraphrase of Psalm 12. The cantata was first published in 1851, as No. 2 in the first volume published by the Bach Gesellschaft.