Abu Bakrah (R.A.) narrated that the Prophet (PBUH) said:
“Time has turned back to its original state (and reached its full cycle) as it was when Allah created the Heavens and the Earth. There are twelve months in a year, out of which four months are sacred: Three are in succession; Dhul-Qi’dah, Dhul-Hijjah and Muharram, and (the fourth is) Rajab of (the tribe) of Mudar which comes between Jumada and Sha’ban.”
Imam Muslim also reported on the authority of Abu Bakrah (R.A.) that the Prophet (PBUH) said (in the sermon of the Farewell Pilgrimage),
“Time has turned back to its original state (and reached its full cycle) as it was when Allah created the Heavens and the Earth. The year is of twelve months, out of which four months are sacred: Three are in succession; Dhul-Qi’dah, Dhul-Hijjah and Muharram, and (the fourth is) Rajab of (the tribe) of Mudar which comes between Jumada and Sha’ban.”
Then he asked, “What month is this month?” We said, “Allah and His Messenger know best.” He kept silent for a while until we thought he would attach to it a different appellation. “Is it not Dhul-Hijjah?” he wondered. “Yes, it is.” we said. Then he asked, “What is this town called?” We said, “Allah and His Messenger know best of all.” He was silent for a while until we thought he would give it a different name. “Is it not al-Baldah? (i.e. the town, meaning the sacred town of Makkah),” he wondered. “Yes. It is” we replied. Then he asked again, “What day is it today?” We replied, “Allah and His Messenger know best of all.” Then he kept silent for a while and said wondering: “Is it not ‘an-Nahr’ (i.e. slaughtering) Day?” “Yes. It is.” We said. Then he said, “Your blood, property and honor are all inviolable (Haram). They are sacred and inviolable as the inviolability of this sacred day, in this sacred month, in this sacred town.” “You will surely meet your Lord, Who will ask you about your deeds. So do not turn back, after I leave you (meaning after his death) into disbelievers or as those who go astray and kill one another. Have I not delivered the Message (of my Lord)?” “Yes, you have, “they replied.” O Allah! Bear witness! Let him that is present convey it unto him who is absent. For haply, many people to whom the Message is conveyed may be more mindful of it than the audience.”
Explanation of the Hadith:
The fact that the Prophet (PBUH) is emphasizing that the year is twelve months, is in itself a scientific miracle, because the year of any of the solar system planets, is the period of time taken by a given solar system to complete one revolution around the sun. The duration of this period is determined by the length of the radius of the orbit, i.e. how far the planet is from the sun, as well as the speed at which the planet orbits. Those two facts have not changed since the first moment the heavens and earth were created. Any change in either of these factors would cause a severe disturbance in the order of the solar system, which has been following the same pattern we perceive today for billions of years.
As for the indication of “Turning of Time” stated in the hadith, it is a Divine Revelation from Allah, the Almighty, to the last of His Prophets and Messengers. The Arabs before the advent of Islam invented a trick called “an-Nasi” (the postponement and replacement of the sacred months), i.e. claiming that the month of Muharram (the first month in the lunar calendar) was going to come that particular year, later than its identified time. That was because they wanted to violate its sanctity and fight each other in that month (since it was not the sacred month of Muharram anymore). The months then became extremely muddled, thus Allah, the Almighty, revealed to His Messenger (PBUH), the reality of these months, which are adjusted by locations of the sun and the moon, in addition to the orbiting of the moon round the earth, along with its orbiting round the sun together with the earth.
The expression used by the Prophet (PBUH) when he sailed, ” Time has turned round again as it was when Allah created the Heavens and the Earth,” has an inherent implication to the spherical nature of the universe and all the celestial bodies existing in it. The term “turned round” is a clear indication that the universe has turned back, as it is in circular motion, to how it was when it started.
This also emphasize that time is not a material figure, which circulates round, but rather a period of time, which elapses. So, if time turns round then the whole universe and its celestial bodies are spherical.
The words of the Prophet (PBUH), “as it was when Allah created the Heavens and the Earth”, prove the fact that time has always followed this pattern over the long history of our universe which is estimated to be at least 10 billion years, and it will remain so till the Day of Resurrection by the will of Allah.
Again, the source of this knowledge could only be a Divine Revelation from Allah, Glorified be He, to His Messenger (PBUH).