Translation of the verse 18 from Surah Ar-Ra‘d : Number of verses 43 - - page 251 - Part 13.
For those who answered their Lord's Call [believed in the Oneness of Allah and followed His Messenger Muhammad SAW i.e. Islamic Monotheism] is Al-Husna (i.e. Paradise). But those who answered not His Call (disbelieved in the Oneness of Allah and followed not His Messenger Muhammad SAW), if they had all that is in the earth together with its like, they would offer it in order to save themselves (from the torment, it will be in vain). For them there will be the terrible reckoning. Their dwelling place will be Hell; - and worst indeed is that place for rest.
For those who have responded to their Lord is the best [reward], but those who did not respond to Him - if they had all that is in the earth entirely and the like of it with it, they would [attempt to] ransom themselves thereby. Those will have the worst account, and their refuge is Hell, and wretched is the resting place.
(13:18) There is an excellent reward for those who responded to the call of their Lord. As for those who rejected His call, they would willingly give for their ransom all the wealth the earth contained, if they possessed it, and as much more besides (in order to escape retribution). *33 Those are the people who shall have the heavy reckoning; *34 their abode shall be Hell-a wretched resting place.
*33) This shows that the disbelievers would be in such a sad plight that they would not hesitate to give their alI for their redemption.
*34) ".... they shall have the heavy reckoning": they shall have to bear the full consequences of their evil deeds. No sin, no shortcoming, in short, nothing will be forgiven and no evil shall go un-punished.
We learn from the Qur'an that the rebels of AIIah shall have to render a reckoning, whereas there shall be a "light" reckoning from those who have been faithful and obedient to their Lord. In consideration of their loyal services, their cases will be dealt with leniently, and taking their general goodness into account many of their shortcomings will be forgiven.
This is further amplified by a Tradition of the Holy Prophet. Hadrat 'A'ishah relates, "I said, O Messenger of Allah !the most dreadful verse of the Qur'an is this: Whoso shall commit an evil, he shall be punished for it'. (IV :123). The Holy Prophet answered, O `A'ishah! don't you know how Allah clears the accounts of His faithful and obedient servant? Whatever harm or trouble he receives in this world-even so much as the pricking of a thorn-is taken by Allah as atonement for one or the other of his sins. As regards the Hereafter, everyone, who shall be called upon to render an account of any sin, shall be punished for it' . At this Hadrat `A'ishah asked, `Then what is meant by light reckoning in this verse: Whoso shall be given his `Conduct Register' in his right hand, he will render a light reckoning?' (LXXXIV:?-8). The Holy Prophet answered, `This means merely the presentation of his whole conduct, that is, all his deeds-good and bad-shall be presented before Allah but he shall not be called upon to clear the account of all his deeds; for the one who shall be called upon to clear the whole of his account, shall be totally ruined' . "
The same thing is happening even in this world. A master deals very leniently with his faithful and obedient servant and connives at his minor faults and even forgives his major faults in consideration of his meritorious services. On the other hand, if a servant is proved to be treacherous and dishonest, no consideration is given even to his services, and he is punished both for his minor and for major faults.