Praise be to Allah.

Firstly: 

Allah, may He be glorified and exalted, says (interpretation of the meaning):

“He arranges (every) affair from the heavens to the earth, then it (affair) will go up to Him, in one Day, the space whereof is a thousand years of your reckoning (i.e. reckoning of our present worlds time)”

[as-Sajdah 32:5]. 

Ibn Katheer (may Allah have mercy on him) said: 

Deeds are taken up to the place where they are recorded above the lowest heaven, and the distance between it and the earth is the distance of five hundred years travelling, and the thickness of the heaven is five hundred years. 

Mujaahid, Qataadah and ad-Dahhaak said: The angel descends the distance of five hundred years’ travelling and he ascends the distance of five hundred years’ travelling, but he covers that distance in the blink of an eye. Hence Allah, may He be exalted, says (interpretation of the meaning): “in one Day, the space whereof is a thousand years of your reckoning (i.e. reckoning of our present worlds time)” [as-Sajdah 32:5]. 

End quote from Tafseer Ibn Katheer (6/359). See also Tafseer al-Baghawi (6/300) 

With regard to such matters of the unseen, we must accept what is said about it in the shar‘i text, if it is proven, and we should not ask why or how, because Allah, may He be exalted, is able to do all things; He has encompassed all things in His knowledge and nothing is beyond Him in the heavens or on Earth, and He is not to be questioned about what he does. 

If one of us is able nowadays to contact someone who is at the other side of the world, and can see him and hear his voice at the same time, and if we can see things on our television screens when they are happening, even though there are thousands of miles between us and those events, then how can we wonder or find it strange that the angels descend from heaven then ascend again in one day? For that only happens by the will and decree of Allah, may He be exalted. 

Furthermore, look at what Allah has enabled people to do now of travelling in airplanes of different kinds, and in spaceships. Could the people of old have imagined that humans would travel in such a manner and would cover huge distances so quickly? 

But what is the power of humanity in comparison to the power of Allah, the Most High, the Omnipotent, may He be glorified? He is the Almighty and nothing is beyond Him in the heavens or on earth. He says (interpretation of the meaning):

“The Originator of the heavens and the earth. When He decrees a matter, He only says to it: ‘Be!’ - and it is”

[al-Baqarah 2:117]

“Verily! Our Word unto a thing when We intend it, is only that We say unto it: ‘Be!’ and it is”

[an-Nahl 16:40].

Nothing is impossible for Him and nothing is beyond His power. 

The angels only descend and ascend at Allah’s command. He, may He be glorified, is the One Who enables them to do what they do. 

The angels are a mighty creation, the extent of whose might only Allah knows, and they have powers and abilities which no human can comprehend. 

The Angel of death (peace be upon him) takes the souls of people in a single moment, when some of them are in the furthest west and others are in the furthest east. 

When you understand that it is only Allah Who has bestowed this power on them,

and were it not for Allah, they would not be able to do anything, so in fact their power is to be attributed to Allah, may He be glorified, then you will no longer wonder. 

See also the answer to question no. 843

Secondly: 

In Arabic, the word yawm (day) refers to the period from sunrise to sunset. 

But yawm in Arabic may also refer to time in general, no matter how long it is. For example, in the hadeeth it says: “Before the Hour comes there will be days of harj (killing).” Narrated by al-Bukhaari (7067) and Muslim (2672), i.e., a time of killing.. That does not mean day in exclusion of night.

See: Lisaan al-‘Arab (12/649) 

In al-Misbaah al-Muneer (2/683) it says: The Arabs may say yawm (day) referring to a given moment, whether by night or day. They say “I saved you for this day”, i.e., for this time when I will need you, and they would not see any difference in meaning between that day and that time. End quote. 

Thus Arabic usage indicates that the word yawm (day) may refer to time in general, and that usage is also mentioned in shar‘i texts. Therefore there is no contradiction between linguistic usage and what the text says. 

How beautiful is the report narrated by at-Tabari (may Allah have mercy on him) in his Tafseer (13/602) with a saheeh isnaad from Ibn Abi Maleekah, that a man asked Ibn ‘Abbaas about the Day the length of which is one thousand years. He said: What is the Day the length of which is fifty thousand years? He said: I only asked you so that you would tell me. He said: Allah mentions both of them in the Qur’an, and Allah knows best about them. He did not want to speak about the Book of Allah without knowledge. 

See also the answer to question no. 146979 

Thirdly: 

Getting married in pursuit of chastity is one of the means of getting provision, by the will and decree of Allah. Allah, may He be exalted, says (interpretation of the meaning):

“And marry those among you who are single (i.e. a man who has no wife and the woman who has no husband) and (also marry) the Salihoon (pious, fit and capable ones) of your (male) slaves and maid-servants (female slaves). If they be poor, Allah will enrich them out of His Bounty. And Allah is All-Sufficient for His creatures needs, All-Knowing (about the state of the people)”

[an-Noor 24:32]. 

The Messenger of Allah (blessings and peace of Allah be upon him) said: “There are three whom Allah is bound to help: the mujaahid who strives (in jihad) for the sake of Allah, the mukaatib (a slave who has made a contract of manumission with his master) who wants to pay off his manumission, and a man who gets married, seeking to remain chaste.” Narrated by al-Tirmidhi (1655), classed as hasan by al-Albaani in Saheeh al-Tirmidhi.