These two celebrations are very significant due to what they symbolise. Nauwruz symbolises spiritual renewal and Ramadan symbolises spiritual fasting.
When the Prophet Muhammad was about forty, he received the first divine revelation while meditating during one of the last nights of the month of Ramadan. Years later he received this powerful and impressive message:
“Oh you who believe! Fasting has been prescribed to you as it was prescribed to those who came before you, so that you may be aware [or: “so that you may guard yourselves”] for some numbered days (…) The month of Ramadan is the one in which the revelation of the Qur’an was sent down as a guide to humanity and proofs of the Guide and discernment. Therefore, whoever among you witnesses the month, let them fast. Those who are ill or traveling, let them do it another time for the same number of days. God wishes ease for you, not difficulty, and that you complete the number of days and celebrate God’s greatness for having guided you, such that you may be grateful. When My Servants ask about Me: I am near and I respond to the plea those who plea when they plea to Me. Therefore, let them respond to Me and believe in Me, so that they may be rightly guided.” (Q. 2:182-5)
The eminent Ismaili scholar of the Fatimid period, the qadi al-Nu‘man, explains in his books that the fast, like all other rituals, has two aspects: the outer or exoteric aspect (zahir) and the inner or esoteric aspect (batin). That is to say, the outer fast, which consists in abstaining from food, drink and intimate relations during the day is a symbol for the inner fast. This inner fast is moral, intellectual and spiritual. The moral fast, which consists of keeping away from bad words and deeds, can be best explained through the words of Bibi Fatima, the daughter of the Prophet and the spouse of Hazrat Ali, as cited by al-Nu’man: “Whoever fasts but does not guard their tongue, hearing, sight and limbs, indeed has not fasted at all.” (1) (The Pillars of Islam, I:333). The intellectual fast consists of sharpening our consciousness, sending away bad thoughts and concentrating our attention on our true place in creation. Finally, the spiritual fast consists of elevating ourselves above the exoteric and becoming conscious of our relation to the Imam of the Time, whose role is to explain the true inner meaning of religion and life in general, guiding us towards the Creator.
As a culmination of the month of fasting, we Ismailis commemorate the night of the first revelation (Laylatul-Qadr) on the twenty-third night of Ramadan. This way Ramadan can be understood as a preparation for such a special celebration, in which we recall the contact between the divine and the human which the Prophet first experienced that night, and which our Imams help us to try and achieve.
(1) The Pillars of Islam: Da‘a’im al-Islam of al-Qadi al-Nu‘man (Volume 1) Translated by Asaf Fyzee revised and annotated by Ismail Poonawala (Oxford University Press, 2002).