TaAAruju almala-ikatu warroohu ilayhi fee yawmin kana miqdaruhu khamseena alfa sana (surah Maarij: 4)

Tafseer Tafheem-ul-Quran by Syed Abu-al-A'la Maududi

(70:4) by which the angels and the Spirit *3 ascend to Him *4 in one Day the duration of which is fifty thousand years. *5

Ta`rujul malaaa`ikatu war Roohu ilaihi fee yawmin kaana miqdaaruhoo khamseena alfa sanah

*3) "The Spirit": the Angel Gabriel (peace be on him), who has been mentioned separately from the angels in order to impress his unique glory and greatness. In Surah Ash-Shu'ara' it has been said: "The trustworthy Spirit has came down with this Qur'an upon your heart", (v. 193), and in Surah AI-Baqarah "Say to them: whoever is an enemy to Gabriel, should understand that he has, by .Allah's command. revealed upon your heart this Qur'an." (v. 97). These verses when read together show that Ar-Ruh (the Spirit) implies the Angel Gabriel.
*4) This is an ambiguous theme the meaning of which cannot be determined precisely. We neither have any knowledge of the reality of the angels, nor can understand the nature of their ascent, nar can conceive the stairways on which they ascend. Besides, about AIIah also it cannot be imagined that He lives in a particular place, for He is exalted and free froth the restrictions of space and time.
*5) In Al-Hajj: 47, it has heen said: "These people are demanding of you to hasten the torment; AIIah will never tail to fulfil His threat, but a day with ycur Lord is equal to a thousand years as you reckon." In Surah As-Sajdah: 5, it has been said: "He administers the affairs of the world from the heavens to the earth, and the report of this administration ascends (to be presented) before Him in a Day whose length, according to your reckoning, is a thousand years". And here, in response to the demand for the torment, the measure of Allah's one day has been stated to be fifty thousand years. Then the Holy Prophet (upon whom be peace) has been consoled, saying: "Have patience at the demand for the torment which the people make out of jest and fun," and then it is said: "They think it is far off, but We see it as near at hand." When all these verses are read together, what becomes obvious is: "The people, because of their narrow and restricted outlook, measure the time of Allah's decrees by their own scales of time and, therefore, consider a hundred years or so to be a very lengthy period, whereas in the Divine conduct of affairs there are schemes spreading over a thousand years each, or fifty thousand years each, as you reckon, and this measure also is only by way of example; otherwise schemes in the universe may extend over millions and billions of years as well. Of these one is the scheme under which Mankind has been created on the earth, and a time limit has been set during which it has been allowed to function here. No man can know when this scheme began, what time-limit has been decreed for its completion, what Hour has been appointed for bringing it to an end, when Resurrection will take place, and what time has been fixed for raising all men, born since the beginning of creation till Resurrection, from death simultaneously and calling them to account for their deeds. We only know to some extent that part of the scheme which is passing before us, or a partial history of the past ages which exists with us. As for its beginning and end, to say nothing of knowing it, we do not even have the power to understand it, not to speak of understanding the wisdom which works behind and underlies it. Now the people who demand that the scheme be cut short and its conclusion be brought immediately before them, and if this is not done. they use it for an argument to prove that the universe has no end and conclusion, in fact, present a proof of their own ignorance and folly. (For further explanation, see E.N.'s 92, 93 of Surah Al-Hajj, E.N. 9 of As-Sajdah).