Persian authors have long since been interested in making use of Arabic sayings in their books and treatises, on the one hand, to better express their intended views and, on the other, by doing so, to show off their deep knowledge of Arabic literature. One of such Persian texts- on mystical literature, in particular-, which is counted as a treasure replete with various ideas and topics, is 'Ayn al-Qozat Hamadani's Letters. Nevertheless, because no comprehensive index has been provided for these letters, they have not been benefited from by scholars and researchers as much as they should.The present writer has extracted the Arabic sayings appearing in this source and compared them against important books on Arabic sayings and literature, thus demonstrating that the Qazi 'Ayn al-Qozat has made use of as many as 73 Arabic sayings including, in addition to ancient sayings, some of Movalladun's sayings as well (Movalladun being those Arab poets born in the early time of Islam). About one-fifth of these cannot, however, be found in old Arabic books of sayings and most important books of Arabic literature. The list we have prepared not only adds to the rich treasure of old Arabic sayings but also clearly demonstrates the Qazi's mastery of Arabic literature, showing, to some extent, his sources in writing the Letters, Arabic books of sayings.