A traditional school, or darshana, cannot be “intrinsically heterodox”, though Vedantin that you are I can see what leads you to this question in regard to Mīmāmsā.

The denial of a deity—or rather the suspension of judgment as to whether there is a God or not—is characteristic of Buddhism, as we know, and in the Vedic context couldn’t the “atheism”, or better “non-theism”, of the early Mimamsic authorities to whom you refer simply be tantamount to an affirmation of the penultimacy of every concept of “Lord”?

As for their denial of the yugas, is this anything more than a recognition that though things may seem to be passing through cycles, it cannot really be so, time and flux being features of Māyā? After all, from the “point of view” of the Absolute, to use the uselessness of such a phrase, pralaya and manvantara—“day” and “night” in the “life of Brahmā”—are simultaneous.

You pose a number of questions concerning the Orthodox form.

First, how does a catechumen discern his patron saint? As far as I know there is no single, formulaic answer to this question. Patrons are normally chosen (or are given the opportunity, if you prefer, to choose us) in consultation with one’s priest and based upon an extended, prayerful reading of various saints’ lives, in which a specific affinity may be noticed.

Second, how acceptable is it within Orthodoxy to see all phenomena as manifestations of the Logos and therefore as possessing what you called a “derivative sanctity”? This is not merely acceptable; it is the sine qua non of a genuinely Orthodoxy understanding of the created order. While the Orthodox vision must be sharply distinguished from a Romantic or sentimental appreciation of the natural world, in which a merely passionate pleasure or delight remains uncorrected by ascetic discipline, this discipline or rigor exists precisely in order that the “doors of perception” might be “cleansed” and the radiant presence of the Divine might be encountered in all things. You might usefully read, or reread, a short section called “Through Creation to the Creator” in the chapter on “God as Prayer” in Kallistos Ware’s Orthodox Way.

Third, what should you anticipate when it comes to specific spiritual practices? This is a large question, obviously, but what I can certainly say is that every Orthodox Christian is expected to have a rule of prayer, given him by his spiritual father, whether pastor or otherwise. As for the level of interiority and intensity this practice involves, this will clearly vary from person to person, depending in part on whether his temperament is more jnanic or bhaktic.

I was most intrigued by your fascinating account of the special exhibition of Moghul miniatures at the Metropolitan Museum, particularly the “exquisitely rendered” portrait of the divine Plato—one of four illustrations, you say, for a poetic “Life of Alexander” written by an Indian Sufi—in which Plato is depicted as a hermit living in a cave and being visited by Alexander the Great.

One can’t help but think of Plutarch’s own Life of the emperor. As you may remember, he tells us that Alexander once rebuked his master Aristotle for publishing his “esoteric” books, among them the Metaphysics. Aristotle is said to have replied, reassuringly, that though the books had been published they in fact remained unpublished, since no one not already initiated would understand them anyway!

Just think: if a mere Greek historian could write so intriguingly about an exchange between Alexander and a lowly Aristotle, what wondrous things must have passed between the Great and the Divine as reported by an Indian Sufi?!