Al Bukhari(R.A.) recorded the following hadith in his Sahih from Abu Huraira(R.A.), in the chapter on the virtues of the Quraan:
Narrated Abu Huraira(R.A.): Allah's Apostle(sallallahu alaiyhiwassallam) deputed me to keep Sadaqat (Al-Fitr) of Ramadan. someonecame and started taking handfuls of the foodstuff (of the Sadaqa)stealthily. I took hold of him and said, "By Allah, I will take you toAllah's Apostle(sallallahu alaiyhi wassallam) ." He said, "I am needyand have many dependents, and I am in great need." I released him.


In the morning Allah's Apostle(sallallahu alaiyhi wassallam) askedme, "What did your prisoner do yesterday?" I said, "O Allah's Apostle !The person complained of being needy and of having many dependents, so,I pitied him and let him go."


Allah's Apostle(sallallahu alaiyhi wassallam) said, "Indeed, he told you a lie and he will be coming again."


I believed that he would show up again as Allah'sApostle(sallallahu alaiyhi wassallam) had told me that he would return.So, I waited for him watchfully. When he (showed up and) startedstealing handfuls of foodstuff, I caught hold of him again and said, "Iwill definitely take you to Allah's Apostle(sallallahu alaiyhiwassallam) . He said, "Leave me, for I am very needy and have manydependents. I promise I will not come back again." I pitied him and lethim go.


In the morning Allah's Apostle(sallallahu alaiyhi wassallam) askedme, "What did your prisoner do." I replied, "O Allah's Apostle! Hecomplained of his great need and of too many dependents, so I took pityon him and set him free."


Allah's Apostle(sallallahu alaiyhi wassallam) said, "Verily, he told you a lie and he will return."


I waited for him attentively for the third time, and when he (cameand) started stealing handfuls of the foodstuff, I caught hold of himand said, "I will surely take you to Allah's Apostle(sallallahu alaiyhiwassallam) as it is the third time you promise not to return, yet youbreak your promise and come." He said, "(Forgive me and) I will teachyou some words with which Allah will benefit you." I asked, "What arethey?" He replied, "Whenever you go to bed, recite "Ayat-al-Kursi"'Allahu la ilaha illa huwa-l-Haiy-ul Qaiyum'(Allah, there is noneworthy of worship but He, the Ever Living the One Who sustains andprotects all that exists.) [Surah Al Baqarah Ayah 255 (Ayat-ul-Kursi) ]till you finish the whole verse. If you do so Allah will appoint aguard for you who will stay with you and no satan will come near youtill morning. " So, I released him.


In the morning, Allah's Apostle(sallallahu alaiyhi wassallam)asked, "What did your prisoner do yesterday?" I replied, "He claimedthat he would teach me some words by which Allah will benefit me, so Ilet him go."


Allah's Apostle(sallallahu alaiyhi wassallam) asked, "What arethey?" I replied, "He said to me, 'Whenever you go to bed, reciteAyat-al-Kursi from the beginning to the end "Allahu la ilaha illahuwa-lHaiy-ul-Qaiyum".' He further said to me, 'If you do so, Allahwill appoint a guard for you who will stay with you, and no satan willcome near you till morning.'


(Abu Huraira(R.A.) or another sub-narrator) added that they (the companions) were very keen to do good deeds.


The Prophet(sallallahu alaiyhi wassallam) said, "He really spokethe truth, although he is an absolute liar. Do you know whom you weretalking to, these three nights, O Abu Huraira?" Abu Huraira(R.A.) said,"No." He said, "It was Satan." [Sahih Al-Bukhari Volume 3, Book 38,Number 505]**********************


Ayat-ul-Kursi is described as the greatest Ayah in the Quraan.
Imam Ahmad(R.A.) recorded that 'Ubayy bin Ka'b(R.A.) said that theProphet (sallallahu alaiyhi wassallam) asked him about the greatestAyah in the Book of Allah, and 'Ubayy answered "Allah and his Messengerknow better." When the Prophet(sallallahu alaiyhi wassallam) repeatedhis question serveral times, Ubayy(R.A.) said "Ayat-ul-Kursi" TheProphet(sallallahu alaiyhi wassallam) commented, "Congratulations forhaving knowledge, O Abu Al-Mundhir! By He in whose Hand is my soul!this Ayah has a tongue and two lips which praises the King (Allah) nextto the leg of the throne." [Ahmad 5:14] [Muslim 1:556 ]


VIRTUES OF AYATUL KURSI:
This is the most lofty Ayat of the Qur'an -e-Kareem.
That is the chief Ayat of the Qura'an-e-Kareem.
The reader is protected from the evil effects of Jinn from morning till evening and from evening until morning.
It is from the threshold of the Arsh(Throne).
It is equal to a quarter of the Qur'an(in reward).
Whoever recites after the Fard salaat will be protected until thenext salaat and reciting it constantly was done by the Nabi, Siddiqueor martyr and only death is the barrier between the reader andJannat(Paradise).
Blowing it upon food and drink brings blessings and abundance.
It is greater(in value) than the skies, earth, Jannat and Jahannam.
Whosoever reads it upon entering the home, satan flees from that home.
The reciter, his children, home, wealth, property and the homes of his neighbours are safe.
Whosoever reads it together with the last Ayats of Surah Baqarah, shaytaan does not enter his home for three days.
The Jinn cannot open any utensil upon which it is read.
In it is the Ism Azam(Blessed name of Allah; through which the invokers duaa is fulfilled).
When reciting it whilst retiring to one's sleeping place, one isprotected until the morning. Two Angels are deputed to protect thatperson.
Whosoever recites it after every Fard salaat, will be rewardedwith a grateful heart, a remembering tongue, the reward of beingmartyred in the path of Allah, and will also be rewarded like theSiddiques.
When one reads it and blows on his possessions and goods, then shaytaan will not come near.