After some of his early Zen retreats, Kennedy says that he was so impressed with "the value of the meditation experience when it was guided by the inspirational leadership of Zen teachers that I believed it belonged in the church."
Here are some quotes:
those Christians who are tempermentally inclined toward practicing Zen to enrich their lives
no one devotional practice possesses the whole Christ
(these Zen gifts can make us better Christians)
(these Zen gifts) offer us a spiritual experience rather than a theory
(Zen practice for Christians may involve an) apostolic endeavor to listen attentively to the other in an attitude of respect and admiration at how truth manifests itself differently in other cultures and pesonalities
Quotes about the ten Ox-herding pictures:
(the ten bulls represent the) successive steps we must take to realize one's true nature
Kennedy uses the ox-herding pictures, the corresponding verses, related koans, and Western prose/poetry to reveal insights into the ten steps.