For years, according to Fr. John Walsh, Maryknoll missioners have gone out "armed with seminary notes and skills and oozing righteousness, prepared to give but not to receive, to teach but not to learn." And most found out, often to their great chagrin, that "mission was a two-way street." Mission means carrying the good news of the Gospel to the four corners of the world but it also means taking on wisdom and knowledge from the people--about building...