56 Unquestionably, so as not to close against themselves the road to justice and peace through these false tenets, both parties ought to have been forewarned by the wise words of Our Predecessor: "However the earth may be apportioned among private owners, it does not cease to serve the common interests of all." This same doctrine We ourselves also taught above in declaring that the division of goods which results from private ownership was established by nature itself in order that created things may serve the needs of mankind in fixed and stable order. Lest one wander from the straight path of truth, this is something that must be continually kept in mind.
Source: Quadragesimo Anno (Vatican.va)