"Lead, Kindly Light, amid the circling gloom..."
This line, from John Henry Newman's hymn, "The Pillar of Cloud," is one of today's selections because he was baptized on this day in 1845. Faith is this day's theme, hence the greatest hits collection of 1,500 years of Christian hymns.
While the sacred writings section of the Harvard Classics is admirable for its corporation of selections from all the world's major religions, the set as a whole is still the product of a white, male, Anglo-Saxon, Protestant world. Christianity, particularly the protestant variety, was the one true faith of the ruling class. The other faiths seems to be included for their similarities to Christianity, not for their differences.