In October, Pope Francis will convene a worldwide synod of bishops and heads of religious orders to discuss the faith, young people, and vocations. To prepare for this gathering, we are going to feature three stories focusing on vocation and discernment. This month, we focus on the vocation to evangelization and catechesis by looking at Nicholas Black Elk, a layperson who brought Christ to his own people, the Lakota of South Dakota. In coming issues, we will highlight vocations to the priesthood and married life.