Marko Rupnik’s In the Fire of the Burning Bush is an exposition of the Christian life by a Roman Catholic in terms of Eastern Orthodoxy. The book is rich, evocative, and penetrating.

Anyone who desires to anchor theology and praxis in “deep ecclesiology” or in the great traditions of the Church can find much that useful here. But, dont’ expect to skim it; the book requires pondering and pondering leads to worship.
The spiritual life is christological: “Christ fully reveals humanity to itself and brings to light its very high calling” (40). “Christ is the primordial Word of life that remains for us to touch and taste, because in his body he has made that absolute Love that escapes humanity in the abysses of Trinitarian Love visible” (40). [Read that carefully; the syntax is thick but it is good.]
“The Body of Christ is what is absolutely spiritual in the cosmos and in humanity” (41).
“It is in his Passion that the true meaning of the spiritual is found” (41).
The Eucharistic dimension of the spiritual:
“The sacrament makes history, creation, and humanity itself Christlike” (42). “… a piece of bread narrates to us the whole history of Christ” (42).
Finding God in all things [a favorite theme of Eastern Orthodoxy]:
“Knowledge gravitates around the notion of object, but only love can decentralize us in some way, making us consider the other as subject” (45). “In the Eucharistic wake … things … light up before us like the burning bush of Moses in the desert.”
Knowledge asks “what is this?” To the question “What is this?,” Love whispers “Who is here?” (45).
“The ultimate destiny of creation and of history is to become a spiritual reality, a theophanic, Christ-bearing reality” (46).