“[O Muhammad!] Tell them: ‘I only warn you by the Revelation.’ But the deaf do not hear the cry when they are warned. Were only the slightest whiff from your Lord’s punishment to touch them, they would cry out: ‘Woe to us; we were indeed wrong-doers.’ We shall set up just scales on the Day of Resurrection so that none will be wronged in the least. (We shall bring forth the acts of everyone), even if it be the weight of a grain of mustard-seed. We shall suffice as reckoners.”
(Al-Qur’ān – 21:45-47)
The verse 21:45 refers to God’s punishment which the unbelievers sarcastically requested should strike them soon. While the verses 21:46-47 talk of the Day of Resurrection, when each and every person will be awakened and asked about his deeds they had done during their stay on earth.
There will be a Balance or Just Scales to weigh the deeds, good or bad, of human beings. It is however difficult to say what the exact form and nature of the Balance will be. This much is certain: that it will weigh good and bad deeds and thereby indicate precisely the moral worth of every person. God uses a familiar word – balance – to explain this purpose. God’s just balance will also evaluate man’s record of life, definitely pronouncing what was predominant in it – whether goodness or evil. The balance is just to ensure that no injustice will be done to anyone, and no act whether the weight of a grain of mustard-seed could escape.