A conversation at the breakfast table this morning led to mention of E.V. Wright’s Gadsby (1939), a novel of no insignificant length that gets by without the letter E throughout its 50,000+ words. (I’ve not read it, but it’s apparently in print and buyable. Note also Georges Perec’s 1969 French novel, La Disparition, with several translations.) Avoiding this or that letter is a kind of constrained writing called a lipogram, but other kinds of constraint include palindromes, alliteratives, univocalism, attention to etymological source (e.g. avoiding latinate words in English), and acrostics. Meter and rhyme are the most typical constraints in much poetry.
These and other constraints, of course, are generally not limited to one particular language, although their application might be more difficult in some languages than others. Other than the meter (5-syllable, 7-syllable, and 12-syllable) and, more occasionally, rhyme, Syriac poetry offers (at least) two kinds of constrained writing, one common and the other rare: 1. the acrostic and 2. having lines or line-pairs that begin and end with the same letter. (I have tried but failed to come up with a concise name for № 2.)
Acrostic poems are well known in various languages, including English, but here we are mainly concerned with alphabetic acrostics. (For Hebrew, see the discussion, with several examples, of W.G.E. Watson, Classical Hebrew Poetry, 190-200, with bibliography, and for later examples see T. Carmi, The Penguin Book of Hebrew Verse, e.g. 206-207, 221-223, 223-224, 233-234, 235-238.) In Syriac, alphabetic acrostic poems, both mēmrē and madrāšē, are plentiful. Ephrem provides many early examples of strophic (as opposed to stichic) acrostics, and Andrew Palmer has studied them (see bibliography below). The hymn Res. 1 is not an alphabetic acrostic, but actually spells out Ephrem’s own name in the beginning strophes and then follows with strophes that all begin with M (vocalized text and ET in Brock and Kiraz, 80-95). The hymn Nis. 1 is an alphabetic acrostic, but it generally skips every other letter, the exception being the sequence P-Q (ʾ g h z ṭ k m s p q š; text and ET in Brock and Kiraz, 224-245). There are also other patterns, even reaching across several poems: № 7-15 of the hymns on Abraham of Qidun (ed. Beck, CSCO 322) follow the alphabet from start to finish with varying numbers of stanzas given to each letter.
We also find acrostics in dialogue poems, e.g. in text 3 of the collection published by Brock (pp. 13-14) we have, after a proem, each speaker beginning a line following the order of the alphabet up to ḥ, at which point the rest of the poem is lost. Several other texts in the collection (e.g. texts 8, 9) follow the same pattern and are complete. There are countless other acrostic poems in later Syriac literature, many still unpublished.
The other kind of constrained writing in Syriac poetry I would like to point out has two examples from the hand of Yaʿqub (Severos) bar Šakko (d. 1241) of Barṭelle. (See Martin and Sprengling in the bibliography for his discussions of poetry.) These verse letters have been known about, but they have not been published or translated, as far as I know. There are two copies of them both at HMML in almost identical manuscripts, even down to the pagination, copied by Dolabani (ZFRN 40 and CFMM 144). The first (pp. 261-263 in the mss) is “A Letter to Rabban Mar Faḫr al-Dawla bar Tomā” and the second (pp. 264-268) is “A Letter to Rabban Abū Ṭāhir Ṣāʿid, known as Tāǧ Al-Dawla bar Tomā of Baghdad”. The constraint in both texts, aside from the 7-syllable meter, is that each poem has each of its couplets beginning with the same letter, P in the first case, T in the second. Here is the beginning of the P-poem:
Here are the first four 7-syllable lines (copied two to a line in the manuscript) in English:
I have stretched out my neck in righteousness,
That I might bow before [his] feet.
I have opened my mouth that I might greet
Him who chases away every bad thing.
And now an example from the T-poem:
tāgāra (h)w da-myattrātā
d-šuprēh nābaʿ galyāʾit
tēʾaṭron (h)u d-ḥasyutā
wa-gmir b-kol-znā mpattkāʾit
He is a merchant of excellent goods,
Whose virtue springs up openly.
He is a theater of holiness,
And perfect in every way with variety.
The T-poem has its lines ending in adverbs in -āʾit, and similarly pp. 205-208 of these same two manuscripts have a mēmrā on fasting by John Ismaʿil (d. 1365 according to the manuscript), Patriarch of Antioch and nephew of Ignatius b. Wahīb (on whom see Graf, GCAL II: 271), in which every line of the poem ends with an adverb in -āʾit.
These Syriac authors show the depth of their knowledge of the language in being able to construct poems in these forms, and students may find their practice sharpened by studying these texts more closely. It may be easy to get caught up in the formalism of poetry with acrostic or other letter-focused features, but as a reading of the examples singled out here will show, this is not mere form — not that that’s always a bad thing. Plenty is still said here, and said well.
Bibliography (incl. basics for Syriac poetry)
Bickell, G. “Noch ein Wort über alphabetische und akrostichische Lieder Ephräms.” ZDMG 26 (1872): 809-811.
Brock, S.P. “The Dispute Poem: From Sumer to Syriac.” Bayn al-Nahrayn 7  (1979): 417-426.
________. Sogyātā mgabbyātā. Holland, 1982.
________. “Syriac Dialogue Poems: Marginalia to a Recent Edition.” Le Muséon 97:1-2 (1984): 28-58.
________. “An Acrostic Poem on the Soul by Jacob of Serugh.” Sobornost 23:1 (2001): 40-44.
________. “Poetry and Hymnography (3): Syriac.” Pages 657-671 in The Oxford Handbook of Early Christian Studies. Edited by S.A. Harvey and D.G. Hunter. Oxford, 2008.
Brock, S.P. and G.A. Kiraz. Ephrem the Syrian: Select Poems. Eastern Christian Texts 2. Provo, 2006.
Cardahi, G. Liber thesauri de arte poëtica Syrorum nec non de eorum poetarum vitis et carminibus. Rome, 1875.
Geiger, Abraham, “Alphabetische und akrostichontische Lieder bei Ephräm.” ZDMG (1867): 469-476.
Hölscher, G. Syrische Verskunst. Leipzig, 1932. Rev. by G. Bergsträsser in Orientalistische Literaturzeitung 36 (1933): 748-754.
Kirschner, B. “Alfabetische Akrosticha in der syrischen Kirchenpoesie.” OC I, 6 (1906): 1-69; 7 (1907), 254-291. (As a monograph: Alfabetische Akrosticha in der syrischen Kirchenpoesie. [Rome, 1907].)
Martin, J.-P.P. De la métrique chez les Syriens. Abhandlungen für die Kunde des Morgenlandes 7.2. Leipzig, 1879.
Palmer, A. “St Ephrem of Syria’s Hymn on Faith 7: An Ode on His Own Name.” Sobornost / Eastern Churches Review 17:1 (1995): 28-40.
________. “Words, Silences, and the Silent Word: Acrostics and Empty Columns in Saint Ephraem’s Hymns on Faith.” PdO 20 (1995): 129-200.
________. “Akrostich Poems: Restoring Ephraim’s Madroshe.” The Harp 15 (2002): 275-287.
________. “Restoring the ABC in Ephraim’s Cycles on Faith and Paradise.” JECS 55:3-4 (2003): 147-194.
Schlögl, N. “Das Alphabet des Siraciden (Eccl. 51, 13-29). Eine textkritische Studie.” ZDMG 53 (1899): 669-682.
Sprengling, M. “Antonius Rhetor on Versification, with an Introduction and Two Appendices.” American Journal of Semitic Languages and Literatures 32:3 (1916): 145-216.
________. “Severus bar Shakko’s Poetics, Part II.” American Journal of Semitic Languages and Literatures 32:4 (1916): 293-308.