Robust themes of warfare pervade the Psalter and, through it, the Reformed Protestant tradition.
Our Reformed forefather’s favourite metaphor for the Christian life was that of warfare. Nearly every Psalm refers to the conflict between the righteous and the wicked (148 of 150 by one count), a theme which is almost nonexistent in modern hymns. One author has said, ‘When iron was in men’s souls, and they needed it in their blood, they sang Psalms.’ The Psalms will stiffen a church accustomed to accommodation and compromise with the world. (Terry Johnson, ‘Why Sing the Psalms?’)
Likewise, I’m sure the Psalter both produced mediæval culture and expressed it. But how?
Crusades and Psychomachia come to mind. But I think I’ll have to leave this off to future investigation of the St Albans Psalter, how exactly it’s related to the Crusades and to the anchoritic psychomachia genre.