Miserere Mei: Getting to know the text

On another thread, someone asked about getting a nice setting of Miserere Mei, which is Psalm 50 - a text that is central to the life of a Catholic in Lent. There is no need for a fancy polyphonic setting. The simplicity of the Psalm tone here, calmly and musically sung, is so incredibly beautiful. The Schola can lead the way for the whole parish. Here is one setting from a 1925 Franciscan Processionum.