Aayatul-Kursi And Its Meaning

[From Commentary on Imaam ibn Taymeeyah’s Sharhul ’Aqeedatil-Waasitiyyah By Shaykh Muhammad bin Saalih Al-’Uthaymeen]

Allah says:

Allah! Laa ilaaha illaa Huwa (none has the right to be worshipped but He), the Ever-Living (Al-Hayy), the One Who sustains and protects all that exists (Al-Qayyoom).
Neither slumber, nor sleep overtake Him To Him belongs whatsoever is in the heavens and whatsoever is in the earth.
Who is he that can intercede with Him except with His permission?
He knows what happens to them (His creatures) in this world, and what will happen to them in the Hereafter.
And they wilt never encompass anything of His knowledge except that which He wills
His throne extends over the heavens and the earth, and He feels no fatigue in guarding and preserving them
And He is the Most High (Al-‘Aliyy), the Most Great (Al-‘Atheem).
[Soorah Al-Baqarah (2) Aayah 255]
This great verse incorporates the three types of Tawheed. It includes a number of names and attributes, each of which represents one of the foundations of the creed of Islam:
Allah's saying "Allahu Laa ilaaha illaa Huwa" establishes the principle of Uloohiyyah, which is itself the foundation of Tawheed, and from which stems Islam's attitude to life in general. This principle obliges us to be worshipers of none but Allah. Man should direct his service, worship and obedience to Him alone, adjudicate only by this laws and derive his values, ethics and ideas only from Allah.
Al-Hayy ul-Qayyoom - “The Ever Living, the One Who sustains and protects all that exists", has confirmed two of His great names.

• Al-Hayy - The Ever-Living is He who has a continuous life with no beginning or end. Allah is ascribed with a life that is self-sustaining. It has no external source, unlike the lives of creatures that have been granted to them by the Creator. As He was, together with His attributes, before all else, so shall He remain throughout endless time. 
• Al-Qayyoom - The One Who sustains and protects all that exists. It is He who sustains the lives of creation and manages all the conditions of the universe. He oversees everything: provides for it, preserves it, watches over it, manages it in the way and for the purpose that He pleases.

These two names "the Ever Living, the One Who sustains and protects all that exists" are among the greatest of Allah's beautiful names. Upon them, the rest of His names are based and around them all their meanings revolve. Allah’s being Alive requires all attributes of perfection, because any lacking of an attribute of perfection originates from the weakness of life. Therefore, if Allah has perfect life, He necessarily has all perfection.
Ibn Uthaimeen mentions.
“Furthermore Allah’s hayaat is characterized by the perfection of Attributes: hearing, sight, knowledge, ability, might and all qualities of perfection.”
[Sharhul ’Aqeedatil-Waasitiyyah By Shaykh Muhammad bin Saalih Al-’Uthaymeen]
The attribute of "the One Who sustains and protects all that exists" incorporates His perfect self-sufficiency and His perfect omnipotence. He does not need help from anybody in any way, and every creature depends on Allah's existence and management.
These two names have a great effect on the life of every Muslim who believes in them and comprehends their meanings. His conscience becomes constantly aware of Allah, in worship, love and obedience; for he knows that his Lord sustains his own life and the entire universe, in accordance with His Wisdom and plan. The servant thus adheres to the system Allah designed for his life, Islam, from which he derives his values and criteria and seeks guidance for his actions in all circumstances.
Allah's saying:
"Neither slumber, nor sleep overtake Him" is a reiteration of the fact that Allah is the Sustainer of everything. Slumber and sleep contradict the quality of complete and perfect life and the attribute of the Self-Subsisting because sleep is only required of the creature who gets tired and needs rejuvenation and rest.
Allah’s saying:
"To Him belongs whatsoever is in the heavens and whatsoever is in the earth" confirms His ownership of all things. Allah enjoys an unfettered and absolute authority over His possessions, which He shares with no other being. Belief in those facts, once it takes root in the heart, has an immensely beneficial effect on a believer's life.
Allah's saying:
"Who is he that can intercede with Him except with His permission?" makes clear the status of Lordship (Ar-Ruboobiyyah) and worship. Every human being is a servant of Allah. He does not exceed the boundaries of that status and therefore cannot intercede with Allah without His permission. Our faith (‘aqeedah) thus makes a clear distinction between the nature of the Supreme Creator and His worshippers. They neither mingle nor do they have a single characteristic in common. None can intercede except by Allah’s Permission: His Leave is universal. Even Muhammad (sallallahu ‘alaihi wa sallam) who has the greatest rank with Allah cannot intercede except with the prior leave from Allah. He will be granted this permission after he (r) prostrates before Allah and praises Him with the great praises and glorifications which Allah guides him to it on that day. Then it will be said:Raise your head and speak; you will be listened to, intercede and our intercession will be accepted.
[Saheeh Al-Bukhaari (Arabic/English)], vol. 6, no. 3 and no. 236.]
[It is known] that no one have a rank with Allah greater than that of the Messenger [Muhammad], nevertheless, he (sallallahu ‘alaihi wa sallam) cannot intercede except with the prior leave of Allah.
Allah says:
"He knows what happens to them (His creatures) in this world, and what Will happen to them in the Hereafter. And they will never encompass anything of His knowledge except that which He wills". This is a confirmation that His knowledge encompasses all time and place and things. It is also a reference to the weaknesses of human beings and the limitations of their knowledge which does not exceed that which Allah wishes them to know. A Muslim's awareness of this fact makes him ever-conscious of his Lord, mindful of the limits of behavior and conduct He has set, and quick in turning to Allah in gratitude and repentance. It also makes him avoid arrogance and self-satisfaction.
Allah's saying:
"His Kursi (footstool) extends over the heavens and the earth, and He feels no fatigue in guarding and preserving them" is proof of the completeness of His power. The size of the Kursi (as explained in the authentic hadeeth) is in comparison to the ‘Arsh (Throne) that of a person’s ring thrown into a vast desert.
Allah concluded this great verse by mentioning two of His beautiful names: And He is the Most High (Al-‘Aliyy), the Most Great (Al-‘Atheem). 

• Al-‘Ali [The Most High] means that He is High and Exalted above His creation. No one transgresses by trying to rise to His status without being reduced to humiliation in this world and disgraced with punishment in the Hereafter.
• Al-‘Atheem [The Most Great] means that all greatness is Allah's, and that nothing is of equal status with Him, but everything is below Him. When man becomes aware of Allah's greatness and Exaltation, he realizes his own worth and settles in the station of worship of his Lord. He does not transgress against Allah's bounds, but fears Him, obeys His commands, and rectifies his conduct towards Him and towards His creation.

These then are some of the facets of the greatness of this verse. Each Muslim should learn it by heart, contemplate its meanings and recite it often. There are many Ahaadeeth relating to its excellence and merits. One is a long hadeeth narrated on the authority of Abu Hurayrah (radiallahu ‘anhu) in which the Prophet (sallallahu ‘alaihi wa sallam) was reported to have said to him: "When you go to your bed, you should recite Aayatul-Kursi) from the beginning to the end, by reciting it there will be posted a guardian over you from Allah who will protect you during the whole night and the devil will not be able to come near you till morning."
[Al-Bukhaari]
And on the authority of Ubayy Ibn Ka’b (radiallahu ‘anhu) who reported that the Prophet (sallallahu ‘alaihi wa sallam) said: "Abul-Mundhir! Do you know which verse of Allah’s Book is the greatest?" - Ubayy (radiallahu ‘anhu) replied: "Allah and His Messenger know best" -The Prophet (sallallahu ‘alaihi wa sallam) then asked "Abul Mundhir! Do you know which verse of Allah's Book is the greatest?". Ubayy Ibn Ka'b (radiallahu ‘anhu) said: "Allah! Laa ilaaha illaa Huwa (none has the right to be worshipped but He) the Ever Living, the One Who sustains and protects all that exists. Neither slumber, nor sleep overtake Him." Thereupon the Prophet (sallallahu ‘alaihi wa sallam) struck me on the chest and said: "Felicitation on your knowledge, O Abul-Mundhir."
[Muslim]