Many complaints from prudent and pious men reached the Pope about the
omission of psalms, which took away from those bound to recite the
Office not only helps, well suited for God's praises and for the
expression of their inmost souls, but also diminished that desirable
variety in prayers which is so appreciated and which so well accords
with and aids our worthy, attentive, and devout praise of God. For St.
Basil says that "in smooth uniformity the soul often grows weary and
while present is yet away, but when in psalmody and chant are changed
and varied in every hour, the fervour is renewed and its attention is
restored."

5. This matter of the reform of the order of the psalter was brought
before the Holy See by many bishops and chiefly in the Vatican Council,
where the demand for the old custom of reciting the whole psalter
weekly was renewed, with the provision that any new arrangement should
not impose a greater onus on the clergy, now labouring more arduously in
the vineyard of the sacred ministry on account of the diminution of
toilers. These requests and wishes were repeated to Pope Pius X., and he
took up the matter cautiously, so that the honour due to the cult of the
saints should not be diminished, nor the onus on the clergy increased by
the weekly recitation of the full Psalter. Begging the help of God, the
pontiff formed a commission of learned and industrious men, who with
judgment and care carried out his wishes. The results of their labours
were submitted to the Sacred Congregation of Rites, and after careful
consideration by the members of the Congregation the matter was
submitted to the Pope, who sanctioned the new arrangement, that is, as
regards the order and the division of the Psalms, Antiphons, Versicles
and Hymns, with the rubrics and rules pertaining to the same. And the
Pope ordered an authentic edition of these new arrangements to be
prepared and issued from the Vatican Press.