وَالْوَزْنُ يَوْمَئِذٍ الْحَقُّ فَمَنْ ثَقُلَتْ مَوَازِينُهُ فَأُولَٰئِكَ هُمُ الْمُفْلِحُونَ
The weighing on that Day is true; those whose scales are heavy are the successful. (al-Aʿrāf 7:8)
Thaqulat mawāzīnuhu points to the weight of deeds upon the Balance. The true value of a person's acts will be manifest on the Last Day.