Pahlavi Middle Persian is the language of quite a large body of literature which details the traditions and prescriptions of Zoroastrianism, which was the state religion of Sasanian Iran (224 to c. 650) before the Muslim conquest of Persia.

The earliest texts in Zoroastrian Middle Persian were probably written down in late Sasanian times (6th–7th centuries), although they represent the codification of earlier oral tradition.

[13] Other, less abundantly attested varieties are Manichaean Middle Persian, used for a sizable amount of Manichaean religious writings, including many theological texts, homilies and hymns (3rd–9th, possibly 13th century), and the Middle Persian of the Church of the East, evidenced in the Pahlavi Psalter (7th century); these were used until the beginning of the second millennium in many places in Central Asia, including Turpan and even localities in South India.

[58] Not only did it not display any of the Pahlavi coalescences mentioned above, it also had special letters that enabled it to distinguish [p] and [f] (although it didn't always do so), as well as [j] and [d͡ʒ], unique designations for [β], [ð], and [ɣ], and consistent distinctions between the pairs [x] – [h] and [r] – [l].

Finally, there is a convention of representing 'distorted/corrupt' letters, which 'should' have appeared in a different shape from a historical point of view, by under- or overlining them: e.g. the heterogram for andar 'in' is transliterated BYN, since it corresponds to Aramaic byn, but the sign that 'should' have been b actually looks like a g.[64][65] Within Arameograms, scholars have traditionally used the standard Semitological designations of the Aramaic (and generally Semitic) letters, and these include a large number of diacritics and special signs expressing the different Semitic phonemes, which were not distinguished in Middle Persian.

In order to reduce the need for these, a different system was introduced by D. N. MacKenzie, which dispenses with diacritics as much as possible, often replacing them with vowel letters: A for ʾ, O for ʿ, E for H, H for Ḥ, C for Ṣ, for example ORHYA for ʿRḤYʾ (bay 'god, majesty, lord').

[70][62][63] Since, like most abjads, even the Manichaean script and a maximally disambiguated transliterated form of Pahlavi do not provide exhaustive information about the phonemic structure of Middle Persian words, a system of transcription is also necessary.

In Book Pahlavi, it developed into a peculiar convention, the so-called 'otiose' stroke, which resembles w/n/r and is added to demarcate the end of the word after those letters that never connect to the left: mān' 'house'.

[93] Early Middle Persian inflection as found in the Sassanid rock inscriptions (3rd–4th centuries CE) still retained a minimal case system for the nominal parts of speech, i.e. nouns, adjectives, pronouns and numerals.

[101] For an even more archaic stage, some have claimed that the singular of regular nominals had its own oblique case form, too, and that it was marked by the ending -ē (spelt -y), which still occurs on nouns in Inscriptional and Psalter Pahlavi, albeit somewhat unsystematically.

[96] When they are used as attributive modifers of nouns, however, agreement is optional and, while it remains common in Manichaean Middle Persian, it is increasingly rare in Book Pahlavi, where, e.g. both abārīgān gyāgān (ʾp̄ʾrykʾn gywʾkʾn ) 'other places' and abārīg dēwān (ʾp̄ʾryk' ŠDYAʾn) 'other demons' have been attested.

[115] There are also some irregular or relict forms reflecting more ancient suffixes (comparative -y or -īy or resulting fronting of the preceding vowel, superlative -ist) and/or suppletion:[115][117][113] Manichaean also wahy or wahīy (sp.

[118] The object of comparison for an adjective in the comparative degree is introduced by the preposition az (hc) 'from', the subordinating conjunction kū (AYK) 'where, that'[117] or, more rarely, čiyо̄n (cygwn') 'as':[119] о̄y az/kū/čiyо̄n tо̄ о̄zо̄mandtar (OLE MN/AYK/cygwn' LK ʾwcʾmndtl) 'he is stronger than you.'

[123] In contrast, the enclitic forms can only have oblique functions: i.e., they cannot correspond to the (non-ergative) subject of the sentence,[109] although a few such cases have been attested in late texts, possibly due to New Persian influence.

The exception are the prepositions pad (PWN) 'at', о̄ (OL) 'to' and az (MN) 'from', which do accept the 3rd person enclitic -(i)š, using it both with a singular and with a plural reference, and о̄ then appears as the allomorph aw before -iš: padiš (ptš), awiš (ʾwbš), aziš (hcš).

and has a plural form awarēd (LPNMEyt'),[145] ōrōn (ʾwlwn') 'hither'; ānо̄h (TME) 'there'; nūn (KON) 'now'; ēg (ADYN) 'then, thereupon'; ā- (ʾ) 'then' (normally used with a following enclitic pronoun); hād (HWEt') 'now, then'; pas (AHL) 'afterwards'; pēš LOYN' 'before that, earlier'.

Some common locational adverbs are azabar (hcpl) 'above' and azēr (hcdl or ʾdl) 'below', andarōn (BYNlwn' / ʾndlwn') 'inside', bērōn (bylwn') 'outside',[76] pērāmōn (pylʾmwn') 'around' and parrōn (plwn' 'away, hence').

In general, the apparently random variation of the vowels has been interpreted either as relicts of the inflection of minority stem types or, conversely, as foreshadowings of the New Persian form of the endings.

Verbs for which such forms are attested include daštan (YHSNNtn') 'hold' – dad (dt'), raftan (SGYTWNtn') 'go' – rawd (lpd), burdan (YBLWNtn') 'carry' – bard (bld), čāštan (cʾštn') 'teach' - čāšt (čʾšt'), hōšīdan (hwšytn') 'dry' - hōšt (hwšt') 'dries' and fragendan (plkndn') 'lay foundations' – fragend (plknd).

[187] This has been said to be a relict of the Old Persian imperfect tense, and it has been conjectured that a mysterious Armaeogram HWYTN- occurring in Inscriptional Pahlavi also designates the stem found in this form of the copula.

Some authors[191] identify yet another form, a past pluperfect: The auxiliary būdan is sometimes omitted not only in the 3rd person singular, but even in the plural: u-mān ō padīrag āmad awēšān widerdagān ruwān (APmʾn' OL ptyrk' YATWNt' OLEšʾn' wtltkʾn' lwbʾn') 'and the souls of the departed came to meet us.

also the past tense of an intransitive verb: mardān raft hēnd (GBRAʾn SGYTWNt' HWEnd) 'the men went' Another consequence is seen in the case inflection of nominals, inasmuch as it is preserved.

[196][197][198] Albeit rarely, the verb kamistan 'to want' combined with an infinitive may express future tense: dušpādixšāyīh ī awēšān sar kāmēd būdan (dwšSLYTAyh Y OLEšʾn' LOYŠE YCBENyt' YHWWNtn') 'their evil rule will end', lit.

[201][202] For example, mard ī šahr ka-š kas pad pusīh be padīrēd (GBRA y štr' AMTš AYŠ PWN BREyh BRA MKBLWNyt') 'if somebody adopts a man of the kingdom as his son'; Šābuhr be xandīd (šʾpwhl GHBHWNyt') 'Šābuhr laughed'.

It expresses imperfective and more specifically durative or iterative aspect: kanīzag pad sar ī čāh būd ud ... čahārpāyān rāy āb hamē dād (knyck' PWN LOYŠE y cʾh YHWWNt' ... chʾlpʾdʾn rʾd MYA hmʾy YHBWNt') 'the girl was by the side of the well and was giving water to the animals'.

This form is used attributively more often than the previous one: duxt ī padīriftag (BRTE Y MKBLWNtk') 'an adopted daughter' and is also frequently nominalised: nibištag (YKTYBWNtk') 'something written, a document' (cf.

'; mardōmān ... mizd ī mēnōy bē nē hilišn (ANŠWTAʾn mzd Y mynwd BRE LA ŠBKWNšn') 'people must not relinquish their reward in the spiritual world'.

[212] Nevertheless, they can still be used without an overt agent, resulting in a passive meaning: pus ... ōzad (BRE YKTLWNt') 'the son ... was killed', mardōm ... xwānd hēnd (ANŠWTA ... KRYTWNt' HWEnd) 'the people ... were called'.

Simple negation is found in examples like purnāy (pwlnʾd) 'adult' > aburnāy (ʾpwlnʾd) 'non-adult', dōstīh (dwstyh) 'friendship, amity' > adōstīh (ʾdwstyh) 'enmity', ēr (ʾyl) 'Iranian, Zoroastrian' > anēr (ʾnyl), 'non-Iranian', 'non-Zoroastrian'.

Other verbs used like this, obligatorily or optionally, are sahistan (MDMENstn') 'seem', saz- (sc) 'be proper' (present tense only), šāyistan (šʾdstn') 'be possible', kāmistan (YCBENstn') 'want' (constructed like 'be desirable to s.o.')