Fasting is one of the fundamental acts of worship in Islam. However, today there are significant differences between the fasting times described in the Qur’an and those practiced by the public. These differences arise from interpretations of Qur’anic verses and practices developed throughout history.
In Surah Al-Baqarah (2:187), the time of fasting is described as follows:
> “It has been made lawful for you, on the nights of fasting, to approach your wives. They are a garment for you and you are a garment for them. Allah knows that you used to deceive yourselves, so He accepted your repentance and forgave you. So now approach them and seek what Allah has decreed for you. And eat and drink until the white thread of dawn becomes distinct to you from the black thread. Then complete the fast until the night. And do not approach them while you are in retreat in the mosques. These are the limits set by Allah. Thus does Allah make His signs clear to the people so that they may become mindful.”
This verse clearly defines the beginning and end of the fasting period. The distinction between the white thread and the black thread of dawn refers to the time when night approaches day and light gradually becomes noticeable. This corresponds to the time of the dawn prayer.
The Arabic word as-siyām (الصِّيَام) is derived from the verb ṣāma (صَامَ) and carries the following meanings:
- Fasting – Some claim that fasting is not mentioned in the Qur’an, but the verse explicitly refers to abstaining from eating and drinking. In Arabic it is siyām, in Persian rūze, and in Turkish oruç, all meaning abstaining from food and drink. The Turkish word oruç is historically linked to the Old Turkic verb urmak (to strike), which evolved into oruş, meaning abstention, and later into oruç.
- Self-restraint, abstention – It can generally mean refraining from something or controlling oneself.
- Stillness, inactivity – In classical Arabic texts, it can also mean remaining motionless.
The Distinction Between True Dawn and False Dawn
In Arabic, the word fajr means dawn, and it appears in two forms: - False Dawn (Fajr al-Kadhib): A vertical light rising upward from the horizon in the darkness of the night. This light is not horizontal and disappears shortly after.
- True Dawn (Fajr al-Sadiq): The horizontal spreading of light along the horizon, where whiteness and redness become visible. This corresponds to the Qur’anic distinction between the “white thread” and the “black thread,” and fasting begins at this time.
This distinction is also clarified in hadiths:
> “Eat and drink; do not be deceived by the light that rises vertically, but eat and drink until you see the redness spreading horizontally.” (Abu Dawud, Vaktu’s-Sahur, Hadith No: 2348)
Issues with Modern Time Calculations
Today, the imsak (start of fasting) time determined by official institutions is based on traditional jurisprudential calculations. However, this timing does not fully align with the Qur’anic description.
Traditional calculations often take the sun being 18° below the horizon as the start of imsak.
This corresponds to a time when the sky is still completely dark and the distinction described in the Qur’an is not yet observable.
Historically, these times were based on naked-eye observations, but today technological calculations include precautionary margins, causing fasting to start earlier.
Some institutions, such as the Süleymaniye Foundation, argue that the correct imsak time begins when the sun is at -9°, which aligns with true dawn (fajr al-sadiq) and observable light.
In the time of Prophet Muhammad, there were no clocks; fasting times were determined by observing the position of the sun and natural signs. Hadiths emphasize that the pre-dawn meal (sahur) continues until true dawn becomes visible:
> “Let not Bilal’s call to prayer nor the vertical whiteness deceive you; eat and drink until the light spreads.” (Muslim)
> It is reported that Hudhayfah ibn al-Yaman ate sahur shortly after true dawn began.
These narrations show that the start of fasting should be based on a clearly observable band of light.
The Duration of Ramadan
In Surah Al-Baqarah (2:183–185), it is stated that fasting is prescribed for the entire month of Ramadan:
> “O you who believe! Fasting has been prescribed for you as it was prescribed for those before you, so that you may become mindful… The month of Ramadan in which the Qur’an was revealed as guidance for mankind… So whoever witnesses the month should fast it…”
These verses indicate that fasting is obligatory throughout the entire month, not limited to a few days.
The word Ramadan comes from the root ramida, meaning burning or intense heat. It originally referred to scorching heat. During the time of the Prophet, fasting coincided with a hot season. Later, with the adoption of the Hijri calendar, Ramadan began rotating through different seasons.
Problems in Modern Practice
Modern calendars do not fully reflect the distinction between false and true dawn:
Fazilet Calendar uses 21.5°, resulting in very early times.
Official religious authorities use 18°.
The Süleymaniye Foundation suggests -9°, aligning with observable dawn.
These differences lead to debates, especially regarding sahur and iftar times.
According to the Qur’an, fasting time is based on natural observation. However, modern calculations and precautionary adjustments often cause fasting to start earlier and end later than necessary.
Scientific Benefits of Fasting
Fasting is not only a spiritual practice but also has physical health benefits supported by modern science: - Metabolic Balance: Helps regulate blood sugar and reduce insulin resistance, lowering the risk of type 2 diabetes.
- Autophagy (Cellular Renewal): Discovered by Nobel laureate Yoshinori Ohsumi, this process is activated during fasting, allowing the body to remove damaged cells.
- Heart Health: Lowers cholesterol, regulates blood pressure, and reduces cardiovascular risk.
- Brain Function: Enhances cognitive performance and may protect against neurodegenerative diseases like Alzheimer’s and Parkinson’s.
- Psychological Benefits: Improves mental clarity, stress management, and patience.
- Immune System Support: Promotes renewal of immune cells, increasing resistance to infections.
The fasting time described in the Qur’an can be verified both through natural observation and scientific understanding. When practiced at the correct time, consciously and within healthy limits, fasting becomes both a spiritual and physical source of healing.
Without forgetting that Allah intends ease, every Muslim should observe fasting in accordance with the Qur’an while also considering their physical limits. Reaching accurate knowledge is just as important as acting with sincere intention.
