Pope Leo XIII teaches in his allocution to the Roman Patriciate and Nobility on January 24, 1903:
The Roman Pontiffs have always taken care to equally protect and ameliorate the lot of the humble, and to support and augment the honor of the upper classes. For they carry on the mission of Jesus Christ, not only in the religious order but in the social order as well.
For this reason the Church, while preaching to humanity of the universal filiation from one Father in heaven, recognizes as being equally providential the distinction of classes in society. For this reason she impresses upon her flock that only in the mutual respect of rights and duties and in charity to one another, there lays the secret of just balance, honest well-being, true peace and flourishing peoples.
Thus We too, in deploring the present disturbances troubling peaceful human society, have turned Our gaze repeatedly to the lowest classes, the ones most perfidiously menaced by iniquitous sects, and have offered them the maternal succor of the Church.
Repeatedly, We have declared that the remedy to their ills will never be a subversive equalization of the social orders, but rather that brotherhood which, without disparaging the dignity of rank, unites the hearts of all in a single bond of Christian love. (Leonis XIII Pontificis Maximi Acta, Vol. 22, p. 368).
Plinio Corrêa de Oliveira, Nobility and Analogous Traditional Elites in the Allocutions of Pius XII: A Theme Illuminating American Social History (York, Penn.: The American Society for the Defense of Tradition, Family, and Property, 1993), Documents V, pp. 480-481.