The angels and the spirit ascend unto Him in a Day the measure whereof is (as) fifty thousand years:
The following interpretation of this verse is my personal opinion as I was not able to find a scholarly source to support it:
Meaning of some words in the verse:
The word ‘al-malaika’ (the angels) in this verse can also be interpreted as ‘the forces’. See the following post for an explanation of the word ‘al-malaika’ (forces of nature):
The word ‘the spirit’ (al-ruh) has been understood variously by Islamic scholars. Some think it means ‘inspiration’ (Muhammad Asad); others think it means ‘the soul of a dead person’ as described in the hadith (Study Quran); while classical scholars feel it is a reference to the Archangel Jibreel (Gabriel) who is also named ‘The Trustworthy Spirit’. It could also be a reference to some other Archangel.
The number ‘Fifty Thousand’ in this verse, in my view, is just a metaphorical number referring to ‘very many’ or ‘much’. The Arabs used some numbers to express an indefinite quantity. Among them being 50, 70, 80 and 1000. These numbers all allegorically mean ‘a large quantity’ or ‘an indefinite amount’.
Commentary of verse:
Considering the meaning of the above words the verse can also be translated as:
‘The Forces and the Spirit ascend unto Him (God) in a Period the measure whereof is (as) fifty thousand years’ (Quran 70:4)
“It seems to me that the Multiverse or all existent reality is connected to Allah (God) in an extremely complex way; such that, the affairs of all the worlds are always travelling to God and that there is a basis (law) behind it all. Thus ‘the Forces’ in this verse can be interpreted to mean different types of forces that are connected to God through a law and perform different functions. These forces can also include ‘Angels’ who perform particular tasks related to Mankind.”
An example of this concept is found in the Hadith:
The Sahih recorded that,
When the angels ascend to Allah with the records of the servant’s deeds, Allah asks them, while having better knowledge, “How did you leave My servants?”
They will say, “We came to them while they were praying and left them while they were praying.”
This is because the angels work in shifts with mankind, and they change shifts during the Fajr and `Asr prayers.
The angels who descended will remain with us, while the angels who have remained with us ascend with our deeds.
The Messenger of Allah said, The deeds of the night are elevated to Allah before the morning, and the deeds of the morning before the night falls.
(Tafsir ibn Kathir Vol 1 pg. 111)
According to Ghulam Ahmad Pervez, these functions are performed by different ‘forces’ (See the post: Definition of Malaika [forces of nature]) above.
A second example of this concept is found in another verse of the Quran:
He directs the affair from heaven to earth, then it goes up to Him in one day, whose measure is a thousand years of your counting.
Here the word ‘the affair’ can be understood to mean different forces of nature travelling to God and ‘a thousand years’ once again means ‘an indefinite period of time’.