Praying the Language of Enmity in the Psalter

How is it possible to hold a New Testament ethic to love one''s enemies and pray for their physical infliction, shame, death, and suffering of family members? And yet, the Psalter, the prayer book of the Church, contains such prayers. In modern times, the Church has adopted a semi-Marcionite attitude towards these troubling texts, excluding whole psalms or parts from liturgies and private use. But...