In the Name of God, Most Gracious, Most Merciful

The White & Dark Threads (2:187) - When do we start and break our fasting?

[2:187] Permitted for you is sexual intercourse with your wives during the nights of fasting. They are the keepers of your secrets, and you are the keepers of their secrets. God knew that you used to betray your souls, and He has redeemed you, and has pardoned you. Henceforth, you may have intercourse with them, seeking what God has permitted for you. You may eat and drink until the white thread of light becomes distinguishable from the dark thread of night at dawn. Then, you shall fast until sunset. Sexual intercourse is prohibited if you decide to retreat to the masjid (during the last ten days of Ramadan). These are God's laws; you shall not transgress them. God thus clarifies His revelations for the people, that they may attain salvation.

There are few points that help us understand the statement, "You may eat and drink until the white thread of light becomes distinguishable from the dark thread of night at dawn", in the above verse:

  1. Calculating the time, days, nights, months and years based on the movement of the sun and the moon is a Quranic principal. We understand that from 10:5, 2:189, 6:96, 55:5, 29:61, 11:114, 17:12 and 9:36.
  2. The definition of twilight which is: "The diffused light from the sky when the sun is below the horizon but its rays are refracted by the atmosphere of the earth".
  3. The definitions of the 3 types of twilight:

    - Civil Twilight: Civil twilight is defined when the sun is 6 degrees below the horizon. This is the limit at which twilight illumination is sufficient, under good weather conditions, for terrestrial objects to be clearly distinguished; at the beginning of morning civil twilight, or end of evening civil twilight, the horizon is clearly defined and the brightest stars are visible under good atmospheric conditions in the absence of moonlight or other illumination. In the morning before the beginning of civil twilight and in the evening after the end of civil twilight, artificial illumination is normally required to carry on ordinary outdoor activities

    - Nautical Twilight: Nautical twilight is defined when the sun is 12 degrees below the horizon. At the beginning or end of nautical twilight, under good atmospheric conditions and in the absence of other illumination, general outlines of ground objects may be distinguishable, but detailed outdoor operations are not possible, and the horizon is indistinct.

    - Astronomical Twilight: Astronomical twilight is defined when the sun is 18 degrees below the horizon. Before the beginning of astronomical twilight in the morning and after the end of astronomical twilight in the evening the sun does not contribute to sky illumination; for a considerable interval after the beginning of morning twilight and before the end of evening twilight, sky illumination is so faint that it is practically imperceptible.

    When we read the above three twilight definitions, we find that the Astronomical Twilight is the one that fits best what God states in 2:187 about the white thread of light and the dark thread of the night:

    "You may eat and drink until the white thread of light becomes distinguishable from the dark thread of night at dawn"

    And:

    "Before the beginning of astronomical twilight in the morning and after the end of astronomical twilight in the evening the sun does not contribute to sky illumination; for a considerable interval after the beginning of morning twilight and before the end of evening twilight, sky illumination is so faint that it is practically imperceptible."

    So, the start and the end of the Astronomical Twilight are our times for Dawn and for Night ; Dawn, astronomically, marks the beginning of the day and this is when we start our fasting even though it looks dark all around us. The sky illumination is so faint, then, that it is practically imperceptible. Sunset, astronomically, marks the beginning of the night and we do break our fast and start eating at Sunset even though we still see light.

Now comes the very famous issue for traditionalists: should we rely on our naked eyes or on technology? For the longest time, we have been hearing arguments about "until the white thread of light becomes distinguishable from the dark thread of night at dawn". In the light of the above referenced verses, we see that their arguments about the need to use our naked eyes to determine the time to abstain from eating contradicts the Quran's principal of using "calculations". Why should we rely on our eyesight when we are now blessed with the most efficient technological devices that would provide us with the most accurate calculations. 2:187 is simply describing the physical phenomenon of the crack of the dawn but it does not mandate the use of our eyes and personal judgment. Those who used to do that in the olden days, of course, are not to be blamed. But, what is our excuse of miscalculating that when we are living in this very advanced era?

On a side note, why do Muslims follow the astronomical calculations for the prayer times, but continue to argue and dispute the dark thread of night and the white thread of light or the need of physically sighting the moon to start Ramadan?