As the title suggests, based on the Social Doctrine of the Church, and in particular the Encyclical Letter Fratelli Tutti (2020), this article intends to highlight Pope Francis' pastoral concern for migrants and refugees. His gestures in favor of migrants, as will be seen, “are worth an encyclical”. In view of this, the text provides a brief portrait of historical migrations, which serves as a background for understanding contemporary migrations. These current movements, although in continuity with the migrations of the 19th Century, are marked by characteristics typical of the end of the 20th and beginning of the 21st Centuries. Having done this, the reflection brings into play the nodal points of Fratelli Tutti with a double objective: on one side, ensuring that this encyclical constitutes a kind of second chapter of Laudato Si’ (2015). In effect, while the latter is concerned with the care of “our common home”, that one makes an appeal so that we can all be brothers in this home that is planet Earth. On the other hand, the 2020 encyclical seeks to present in a more concrete way the socioeconomic and political-cultural challenges, as well as the socio-pastoral activities for the effectiveness of this universal fraternity. From the point of view of human mobility, it is about seeking universal and borderless citizenship.