 According to the Rule of St. Benedict (530 AD), Psalm 1 to Psalm 20 were mainly reserved for the office of Prime.In the Rule of St. Benedict, Psalm 9 is sung by the Latin version translated in the Greek of the Septuagint; therein, Psalm includes 18 additional verses in Psalm 10.Benedict divided this joint Psalm 9/10 in two parts, one sung to the end of the "office of Prime Tuesday" () and the other ( and ) earlier on Wednesday.