Ad-Din means the reckoning, the reward or punishment. Similarly, Allah said,

﴿يَوْمَئِذٍ يُوَفِّيهِمُ اللَّهُ دِينَهُمُ الْحَقَّ﴾

(On that Day Allah will pay them the (Dinahum) recompense (of their deeds) in full) (24:25), and,

﴿أَءِنَّا لَمَدِينُونَ﴾

(Shall we indeed (be raised up) to receive reward or punishment (according to our deeds)) (37:53). A Hadith stated,

«الْكَيِّسُ مَنْ دَانَ نَفْسَهُ وَعَمِلَ لِمَا بَعْدَ الْمَوتِ»

(The wise person is he who reckons himself and works for (his life) after death.) meaning, he holds himself accountable. Also, `Umar said, "Hold yourself accountable before you are held accountable, weigh yourselves before you are weighed, and be prepared for the biggest gathering before He Whose knowledge encompasses your deeds,

﴿يَوْمَئِذٍ تُعْرَضُونَ لاَ تَخْفَى مِنكُمْ خَافِيَةٌ ﴾

(That Day shall you be brought to Judgement, not a secret of yours will be hidden) (69:18).''

﴿إِيَّاكَ نَعْبُدُ وَإِيَّاكَ نَسْتَعِينُ ﴾

(5. You we worship, and You we ask for help.) (1:5)