 Jennings became noted for guiding and maturing the St. Olaf Choir from an ensemble rooted substantially in its early twentieth century formation to ascend as ranking among the world's most highly respected choral ensembles.A former student and colleague of Olaf Christiansen, Jennings understood and respected the choir's distinct Lutheran tradition in his programming.However, as the third director of the ensemble, he also modified the tradition of programming exclusively unaccompanied music.