In Early Modern Persian prose and verse, verbs with a present stem accompanied by grapheme "-y" have been used to express modal concepts of imperative and command or invocation and request. Researchers, regardless of the historical changes of Early Modern Persian, believe that this structure of  subjunctive 2^nd person singular has been used to express imperative mood, and that "bâyad" has been deleted from its beginning, and the ending "-y" in these verbs encodes 2^nd person singular. Reviewing the historical background of this structure and mentioning different moods with multiple evidence from Old Iranian languages as well as Zoroastrian Middle Persian, this article concludes that "-y" in the mentioned structure is the remnant of the optative-making morpheme, and that the structure of present stem accompanied by "-y" is the optative mood which indicates the concept of command or invocation.