I know that Maronites are unique even among other Syriac traditions in that we’ve always incorporated the insights of Greek theology with Syriac thought. Who are some of our primary early sources? Fr. Anthony Salim mentions Theodore of Mopsuestia and John Chrysostom.
Untrue, that is not a uniqueness amongst us. The Antiochian tradition was inextricably linked to the Greek East due to geographic and political proximity (hence the presence of Byzantinizations in the West Syriac liturgies much more so than in the East Syriac liturgies). The veneration of Greek fathers is not unique to us. John Chrysostom was originally from Syria (as was Theodore). Reading from the Syriac Orthodox beth gazo, in a hymn that venerates certain Fathers about half are Greek (Basil, John C., Gregory). Pseudo-Dionysius and other Greek Fathers are mentioned within the Syriac Orthodox liturgy elsewhere. The only difference in the same hymn is that we replace Dioscorus with Dionysius and Severus/Clement with Amphilichius.
In addition to those, (generally Syriac and Maronite) hymnology refers to Cyril as the sweet spring or tower of truth, “fiery” Ignatius who is a sea of wisdom (presumably for his epistles), Jacob of Sarug and Ephrem of Nisibis for their extensive writings.
Chorbishop Seely Beggianni mentions Ephrem (the Syrian) of Nisibis and Jacob of Sarug. Are there any other Fathers that we’d “traditionally” turn to?
Or a favorite of Chorbishop Beggiani is John of Apamea. Our uniqueness might be that we actually have
less Greek(-esque) thinkers than the other West Syriac Churches because of our relatively smaller exposure to Greek influences (e.g. Severus, whether monophysite or not, was educated in a typical Greek style and is very philosophical in his writings, unlike the Edessian Syriac Fathers). We made use of Aphrahat “the Sage.” While he’s not necessarily precluded from other West Syriacs, we have more explicit references (as shown by Msgr Seely). There’s also Isaac of Nineveh, whom all of the Western Syriac Churches venerate and read. Bar Hebraeus is almost exclusively Syriac Catholic/Orthodox; his very systematic manner of theology is very “Greek” - he’s commonly compared to Aquinas by Syriacs.
Who else off the top of my head? Athanasius, Origen, Eustasius, and some more particularly Syriac thinkers - Isaac of Antioch, John of Ephesus, Thomas of Marga. This is not meant to be an exhaustive list but show the great expanse of sources, both Greek and not, Antiochene and Edessan, Persian and Alexandrian.
What about our spiritual/ascetic tradition. We like to tout that we are traditionally a monastic/desert spirituality. What are the sources we’d turn to for that? Philoxenus of Mabbugh? Isaac of Nineveh? The Book of Steps? What about the Desert Fathers - who do we typically turn to for that?
Yes, Philoxenus (although excluded from our commemorations for rejecting Chalcedon) and Isaac of Nineveh are sources of Syriac monasticism. As are the Desert Fathers, particularly Anthony (hence the Antonine monks). Of course, all of the West Syriac Churches, and indeed, all the Oriental Churches are “monastic” in origin. There has been a tendency to stress things that are generally Oriental as our uniqueness and not speak of our real uniqueness. Like the fact we reference Antiochene theologians - no one except us would do so. Our prayers are traditionally older redactions than used by the rest of the Antiochene Syriac tradition. Malphono can tell you about our liturgical particularities that express a difference in theological emphasis. Our focus is eschatological, sacramental and penitential.