And the weighing [of deeds] that Day will be the truth. So (7:8)

Almuntakhab Fi Tafsir Alquran Alkarim

The balance of justice on this Momentous Day is truth personified. He, whose deeds of wisdom and piety surpass in weight, shall he and such persons rejoice beyond a common joy

Tafseer Tafheem-ul-Quran by Syed Abu-al-A'la Maududi

(7:8) The weighing on that Day will be the true weighing: *8 those whose scales are heavy will prosper.

And the weighing [of deeds] that Day will be the truth. So meaning

*8). This means that when the Balance is fixed on the Day of Judgement, 'truth' and weight will be identical. The more truth one has to one's credit, the more truth one has to one's credit, the more the weight in one's scale; and vice versa. One will be judged solely on the basis of this weight. In other words, no consideration other than truth will enter into the calculation. A life of falsehood, however long it lasted, and however full of worldly achievements, will carry no weight at all. Weighed in the Balance, the devotees of falsehood will discover that their life-long deeds do not even weigh so much as a birds feather. The same point has been expatiated upon in al-Kahf 18:103-5 : 'Shall We tell you of those who are greatest losers in respect of their deeds? It is those whose efforts have been wasted in this life while they kept believing that they were acquiring good by their deeds. they are those who deny the Signs of their Lord and the fact of their having to meet Him (in the Hereafter). So their works are in vain and we shall attach no weight to them on the Day of Judgement.'
 

And the weighing [of deeds] that Day will be the truth. So meaning in Urdu

اور وزن اس روز عین حق ہوگا جن کے پلڑے بھاری ہوں گے وہی فلاح پائیں گے