Even in its early days, the Congregation was noted for its virtues. Vincent de Paul led his confreres by example and stressed the acquisition of five virtues that would make them effective, Christlike missionaries. These virtues were simplicity, humility, gentleness, mortification, and zeal for souls. Barry Moriarty defines them and explains the necessity for each.
Moriarty, Barry W. C.M. (1994) "Virtues of the Congregation of the Mission," Vincentian Heritage Journal: Vol. 15: Iss. 1, Article 1. Available at: http://via.library.depaul.edu/vhj/vol15/iss1/1