The structure of Masnavi is strangely different from other books written in this style.
Masnavi researcher and scholar Mohammad Ali Movahed has mentioned some points about the strange name of the book and its unique structure, which is as follows:
The name “Masnavi” is odd and the author emphasizes its correspondence with the Quran. In the preface, we read: The name of this book is “Masnavi” and it includes the principles of principles of principles of the religion.
Masnavi is not a books’ name but a kind of Persian poem. This kind of poetry has been used in different formats in many books such as Shahnameh (by Ferdowsi), Vis and Ramin (by Fakhruddin Asa’ad Gorgani), Mantiq ul-Tair (by Attar), Bustan (by Saadi) and Asrarnameh (by Attar). And it is strange for someone to write a book and name it Masnavi.
Elsewhere in the preface, we are surprised to realize that the author considers his book not only one that reveals (the secrets of) the Quran but it seems also one that is its peer. He (Molavi) attributes to Masnabi the same features that the revelation says about the Quran: “As God says, many will be guided by it and many others will go astray (Verse 2 of Surah 26); by noble and pious angels (Verses 15-16 of Surah 80); which none shall touch except the purified. A revelation by the Lord of the worlds. (Verses 79-80 of Surah 56); falsehood does not come to it from before it or from behind it. (Verse 42 of Surah 41).”
With a little contemplation reflection, we come to the point that the naming of the Quran is just as surprising. What Angel Gabriel revealed to the heart of Muhammad (PBUH) was named the Quran and actually quran is not a name of a book but it means “reading”. But the Quran has other names as well, the most important one of which is Kitab. If you look at the words of the Quran, you’ll see that the frequency of the word “Kitab” is much more than that of “Quran”. The word kitab means writing. Hence, our Holy Book is sometimes called writing and sometimes called reading. And these are two generic words. It is a little strange that these two words are used to name a specific book. Just as it is strange that among so many Masnavi books like Shahnameh, Bustan, Asrarnameh, etc, a specific book has been called Masnavi.
But the Quran also has another name that is somehow similar to Masnavi and that makes us reflect more. In two verses, the Quran has been mentioned as Masani: “(Muhammad), We have given you the seven al-Masani (most repeated verses) and the great Quran” (Verse 87 of Surah 15) and “God has revealed the best reading material in the form of a Book with Masani (similar passages) which refer to each other and make the skins of those who fear their Lord shiver” (Verse 23 of Surah 39). And it is surprising that like Masnavi, the word Masani has also been defined as couple, dual, and in its root as repetition.
The reason why Molavi’s book is called Masnavi is both because of the couplet appearance of its verses’ structure and because the two parts in every line of the poem rhyme. This is of course an external feature that can be noticed easily. But the realm of Masnavi’s concepts and content also has a twofold approach which can be seen all over the book in different forms in the confrontations between the worlds of “form and meaning”, “appearance and Batin (inward)”, “world and hereafter”, “body and spirit”, “life and death”, “faith and disbelief”, “earth and heaven”, “determinism and free will”, “light and darkness”, etc. Molavi sees all particles of creation intertwined and formed by contrary, conflicting and contradictory issues.