The Catholic Catechism instructs the faithful that good government has two duties, both of which must be carried out and neither of which can be ignored. The first duty is to welcome the foreigner out of charity and respect for the human person. Persons have the right to immigrate and thus government must accommodate this right to the greatest extent possible, especially financially blessed nations: "The more prosperous nations are obliged, to the extent they are able, to welcome the foreigner in search of the security and the means of livelihood which he cannot find in his country of origin. Public authorities should see to it that the natural right is respected that places a guest under the protection of those who receive him." Catholic Catechism, 2241.
The second duty is to secure one’s border and enforce the law for the sake of the common good. Sovereign nations have the right to enforce their laws and all persons must respect the legitimate exercise of this right: "Political authorities, for the sake of the common good for which they are responsible may make the exercise of the right to immigrate subject to various juridical conditions, especially with regard to the immigrants' duties toward their country of adoption. Immigrants are obliged to respect with gratitude the material and spiritual heritage of the country that receives them, to obey its laws and to assist in carrying civic burdens." Catholic Catechism, 2241.
In January 2003, the U.S. Catholic Bishops released a pastoral letter on migration entitled, "Strangers No Longer: Together on the Journey of Hope." In their letter, the Bishops stressed that, "[w]hen persons cannot find employment in their country of origin to support themselves and their families, they have a right to find work elsewhere in order to survive. Sovereign nations should provide ways to accommodate this right." No. 35. The Bishops made clear that the "[m]ore powerful economic nations…ave a stronger obligation to accommodate migration flows." No. 36.
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