Repentance of the man who committed a hundred murders

Abu Sa'id Sa'd b. Malik b. Sinan al-Khudri says that the Prophet said: "There was a man among a people before you who committed ninety-nine murders. Then he inquired about the most knowledgeable man on earth and he was led to a monk. He went to him and told him that he had killed ninety-nine people and asked him if it was possible for him to repent.

The monk told him: 'NO!' So the man killed him also and completed his hundred. Then he inquired about the most knowledgeable man on earth and was led to a scholar. He went to him and told him that he had killed a hundred people and asked him if there was repentance for him. The man told him, 'Yes. And what can come in between you and repentance?' 'Then he told him, 'Go to such and such a town for in it live people who are devoted to God. Devote yourself there to God in their company and do not come back to your own town for it is an evil place.'

So the man started towards that town. However, while he was halfway through the journey death overtook him. The angels of 'mercy' and 'punishment' descended and began to argue over him. The angels of mercy said: 'This man had repented and was seeking his Lord, (therefore he is our share),' while the angels of punishment claimed that, 'he had never done a good thing in life,' (so he was their share). While they were thus arguing, another angel arrived in the form of a man. They decided to accept him as their arbitrator. He said: 'Measure the earth between the two towns and let him be assigned to the fate of the one he is nearer to.' When they measured they found him nearer to the town he was heading towards. So the angels of mercy took him away."

Another version has it that "he was nearer to the town of the righteous people by just the span of the hand." And another version of a trustworthy report has it that "the earth was ordered to stretch itself to become closer from this end and farther from the other. So that when they measured they found him nearer to the town (of the righteous) by virtue of which he was forgiven."

Now, what can come in between a man and repentance? O you who imagine that your sins are too great - do you think that your sins are greater than those of that man (the murderer of a hundred souls) to whom Allah turned in mercy? Why should you despair? Indeed crimes can be even greater than this and yet they will be forgiven (with true repentance). Consider this,: Says Allah, glorified be He: "(The true servants of Allah are those) who do not call upon another god with Allah, who do not slay the soul Allah has forbidden, save by right, and do not commit adultery. And whosoever does that shall meet the price of sin. His chastisement will be doubled on the Day of Reckoning and he will abide therein for ever - save him who repented, believed and did righteous deeds, such are those whose evil deeds will Allah change into good ones. Allah indeed is very Forgiving, very compassionate." (Al-Furqan:68-70)

Consider the words: "Such are those whose evil deeds will Allah change into good ones." It shows the magnanimity of Allah. And the scholars have said that the changing will be of two kinds. First, change of a man's evil qualities into good ones (in this world itself). For instance of polytheism into monotheism, adultery into chastity, untruthfulness into truthfulness, deceit into honesty, etc. And second, the change of evil deeds into good ones on the day of Judgment.
Also consider the words: "The evil deeds will be changed into good ones." Allah didn't specify whether He will change every evil deed into a good one of equal magnitude. Rather it was left open, and can be lesser, equal, or even greater - depending upon the quality and sincerity of repentance. This is yet another grace from our Lord.

The following hadith brings out this point:

Abdul Rahman bin Jubair narrates on the a Prophet , on whom be peace, (another report suggests that a very old man whose eye-lashes had fallen over his eyes stood before the Prophet supporting himself on a cane), and said: "What will you say of a man who did not leave an evil deed - major or minor - but he committed it. (Another report has it that there wasn't an evil deed that he left uncommitted to the extent that were they to be divided between the people of the world, they would destroy them all). Is there repentance for him?" The Prophet asked him: "Have you embraced Islam?" He said: "Yes! I testify that there is no god but Allah, and that you are His Messenger." The Prophet told him: "Do good deeds (now onwards) and stay away from evil. Allah will change all of them into good ones." The man said: "And my treacheries an debaucheries?" The Prophet said: "Yes (them too)". The man cried out: "Allah is great" and kept repeating until he disappeared from the sight.

Here a repenting man may ask. When I was in error and sins, not even doing my Prayers - an act that severed my links with Islam - I used to do some good things. Will I be rewarded for them after I have repented or are they lost to the winds? The Answer is in another hadith.
'Urwa b. Zubair reports Hakim b, Hizam as saying that he asked the Prophet , on whom be peace: "O Apostle of God! What is your opinion about those good deeds that I used to do in the days previous to Islam, such as spending in charity, liberating a slave, or being good to my relation. Are they to be rewarded for?" The Prophet told him: "It is culmination of those good deeds that led you to Islam."

So, with repentance the sins will be forgiven and evil deeds of the past will be changed into god ones. What more do you want?