In this talk, given on March 24th, 2019, Day 2 of Spring Sesshin at Chobo-Ji, Rinzan Pechovnik Osho examines case #12 of the Mumonkan, "Zuigan Calls 'Master.'" Rinzan investigates the benefits of constraints within the forms of Zen, most fully expressed during intense retreat (sesshin) and how these forms compel us to resolve and go beneath our surface complaints and poisonous defense mechanisms to a large field of love and caring. From the depths of this field, when Zuigan calls out "Master?" who answers?