Marginal notes of any kind, whether by the original scribe or by a later owner or reader, are among the unique parts of a particular manuscript, no matter how many other copies of the main text may exist. Here, as a simple example of such notes, and for those that might like some easy practice reading Garšūnī and Arabic, are two images from SMMJ 168, a collection of homilies attributed to Ephrem, Jacob of Serugh, John Chrysostom, and others in Garšūnī. They are both written by a reader and secondary scribe named Isaac (here spelled Īsḥāq). The first one is in Arabic script:
iġfirū* li-rabbān Īsḥāq
Forgive Rabbān Īsḥāq!
*Missing the alif otiosum.
The second one, several folios later, is written around the outer and lower margin, all in Syriac script (but Arabic language) except for the last three words, which are in Arabic.
hāḏihi ‘l-waǧh katībat al-ʕabd al-ḫāṭiʔ rabbān Īsḥāq bi-sm qass wa-rāhib. taraḥḥam ʕalay-hi wa-ʕalá wāliday-hi ayyuhā ‘l-qānī wa-‘l-qāriʔ. raḥimaka ‘llāhu āmīn.
This side [of the folio] is the writing of the sinful slave Rabbān Īsḥāq, [who is] in name a priest and monk. O owner and reader, plead for mercy for him and his parents! May God be merciful to you! Amen!