The manuscript of the selection of Saʿdī's Dīwān, dated 706 AH and preserved in the Berlin State Library under the catalog number Ms. or. oct. 3451, is one of the earliest extant copies of Saʿdī's works known to have been produced in Shiraz. This present study seeks to analyze the handwriting rules and identify the distinctive features of calligraphy in this manuscript. The necessity of performing this research is extracting the handwriting rules in the aforementioned manuscript in order to simplify the reading of its text for the contemporary reader. Additionally, identifying the specific calligraphic features and distinguishing elements that set this Naskh script apart from more commonly used Naskh of the same period. This research represents a small but meaningful step toward completing and refining the historical narrative of Persian calligraphy. The study is centered around two main questions: 1. What types of handwriting rules appear in the manuscript of Saʿdī’s Dīwān? 2. What are the unique characteristics of the calligraphic rules used in this manuscript?

This research is conducted using descriptive, analytical, and comparative methods. In order to answer questions, first the handwriting rules were categorized into four groups according to modern handwriting. In the second part, five manuscripts dating between 678 and 699 AH were selected for comparative analysis as samples of the current Naskh script of the time. The features of the calligraphy in Berlin’s Saʿdī’s Dīwān were examined in relation to these examples, focusing on letterforms, structural composition, and proportional relationships

The orthography and calligraphy of this manuscript exhibit distinctive stylistic rules. A thorough examination of the text revealed several recurrent orthographic features, including: the attachment of the preposition be (“به”) to the following word, the continuous writing of the plural suffix -hā ("ها"), connected writing of the progressive prefix mi- ("می"); separation of the verbal prefixes be- and na- in the verb didan (“to see”), Continuous writing of specific words, the disjunctive use of verbal prefixes be- and na- (ب‍ - ن‍) in didan (“to see”), the use of tāʾ marbūṭa (ة) in words such as ḥayāt (“life”) and ṣūrat (“form”) and the manuscript lacks a consistent system for dotting Persian letters, sometimes showing variant forms.The calligraphic features of the manuscript are as folloes: The different diacritics of the Naskh script, such as the inverted circles with a sharp edge, the sloping head, and the bowls of the “ج” group, the continuous writing of all the letters of a word, and the “ک” group’s small are unique belonging to the script of the Saʿdī’s Dīwān. Similarities can be seen in both the Signs and the proportions with the last sample of number 5 dated 699 AH. Also, the rule of the baseline is fully observed in it, despite the small dimensions of the Divan of Saadi. The calligraphy of the Saʿdī’s Dīwān contains signs and proportions that distinguish it from the current Naskh script. The manuscript demonstrates a general alignment with the stylistic norms of 8th-century AH Persian handwriting, yet it retains several older features.