According to search-discovered classical Islamic scholarship, the concept of Calendar Events in Islam is rooted in a divinely ordained framework for sacred time. The Quran, in Surah At-Tawbah (9:36), establishes that 'the number of months with Allah is twelve' since the creation of the universe, setting a permanent, unalterable lunar calendar. Classical commentators like al-Qurtubi explain this verse as a declaration that time itself, particularly its division into twelve lunar months, is a divine institution for the sake of human worship. Within this divine calendar, the Quran sanctifies specific periods, such as the four Sacred Months (Dhul-Qa'dah, Dhul-Hijjah, Muharram, and Rajab), the month of Ramadan for fasting, and the months of Hajj for pilgrimage. This structure is not merely for timekeeping but is a spiritual rhythm for the Muslim community, connecting believers to key events and providing regular opportunities for worship, reflection, and renewal, as affirmed by the Prophet ﷺ in his Farewell Sermon which recalibrated human practice to this divine standard.