Links to some excellent online material on the crucial subject (for students of Eliot) of T S Eliot and Christianity. Arranged, very roughly, in order of complexity:
Barry Spurr, T S Eliot's Extraordinary Journey of Faith
Barry Spurr, Suffering Prayer: T S Eliot, his Poetry and his Christianity
Barry Spurr, 'O dark dark dark they all go into the dark: the via negativa in the poetry of T S Eliot'
Lindsay Sarin, Full Circle: T S Eliot's Quest for Spiritual Fulfillment (Honours Thesis)
Florida Gulf Coast University page on Journey of the Magi
Vincent B Leitch, T S Eliot's Poetry of Religious Desolation
Dissertation on Eliot and Religion by Janet MKC (?)
Philip Yancey, T S Eliot's Christian society: Still Relevant Today?
Barry Spurr's findings are treated at full length in his book Anglo-Catholic in Religion: T S Eliot and Christianity
See also earlier blogs on T S Eliot, especially 'Ash Wednesday'.