17 No less grave and no less urgent is another duty: that of the religious and economic assistance of the campesinos (peasants), and in general of that not small portion of your sons forming the population, mostly agricultural, of the Indians. There are millions of souls, they too redeemed by Christ, entrusted by Him to your care and for whom He will some day ask you to render an account; there are millions of individual men often in such sad and miserable living conditions that they have not even that minimum of well-being indispensable to protect their very dignity as men. We conjure you, Venerable Brethren, in the bosom of the charity of Christ to have particular care for these children, to encourage your clergy to devote themselves with ever-increasing zeal to their assistance, and to interest the whole Mexican Catholic Action in this work of moral and material redemption.
Source: Firmissimam Constantiam (Vatican.va)