Seems a strange source for unity.
Cue a VERY brief, but ascertainable nonetheless, mass eye-rolling on Mt. Athos.
Did you miss this sentence?
The Saint of Hippo, a great Father of the Latin Church, is, in fact, of fundamental importance for theology and for the West's very culture, whereas the reception of his thought in Orthodox theology has revealed itself to be rather problematic, the Pontiff said.
To be fair, the article’s title is not reflected in the words quoted from BXVI’s letter. Perhaps it would be best to wait for the contents of the letter to be published in full.
I agree; from what I’ve read of the Orthodox attitude towards Augustine’s writings, a strange choice as a source of unity. More like a source of debate.