127 Those citizens of straitened fortune who are dissatisfied with their very difficult lot in life may be sure that We deeply regret their condition. With respect to social matters: it is Our paternal desire that relations among the various classes come under the guidance, control, and direction of the Christian virtue of justice. We are especially concerned here because the Church's enemies can easily take advantage of any unjust treatment of the lower classes to draw them to their side by false promises and deceptive lies.
Source: Ad Petri Cathedram (Vatican.va)