Allah's statement,

لَهُ مُلْكُ السَّمَاوَاتِ وَالْأَرْضِ وَإِلَى اللَّهِ تُرْجَعُ الأمُورُ ﴿٥﴾

His is the kingdom of the heavens and the earth. And to Allâh return all the matters.

asserts that Allah is the King and Owner of this life and the Hereafter.

Allah said in another Ayah,

وَإِنَّ لَنَا لَلاٌّخِرَةَ وَالاٍّولَى

And truly, unto Us (belong) the last (Hereafter) and the first (this world). (92:13)

Surely, Allah is praised for this attribute, just as He said in other Ayat,

وَهُوَ اللَّهُ لا إِلَـهَ إِلاَّ هُوَ لَهُ الْحَمْدُ فِى الاٍّولَى وَالاٌّخِرَةِ

And He is Allah, La ilaha illa Huwa, all praise is His in the first and in the last. (28:70)

and,

الْحَمْدُ للَّهِ الَّذِى لَهُ مَا فِى السَّمَـوَتِ وَمَا فِى الاٌّرْضِ وَلَهُ الْحَمْدُ فِى الاٌّخِرَةِ وَهُوَ الْحَكِيمُ الْخَبِيرُ

All the praise is Allah's, to Whom belongs all that is in the heavens and all that is in the earth. His is all the praise in the Hereafter, and He is the All-Wise, the All-Aware. (34:1)

Allah owns everything that is in the heavens and earth, and all their inhabitants are servants to Him and humble before Him, just as He said,

إِن كُلُّ مَن فِى السَّمَـوَتِ وَالاٌّرْضِ إِلاَّ آتِى الرَّحْمَـنِ عَبْداً

لَّقَدْ أَحْصَـهُمْ وَعَدَّهُمْ عَدّاً

وَكُلُّهُمْ ءَاتِيهِ يَوْمَ الْقِيَـمَةِ فَرْداً

There is none in the heavens and the earth but comes unto the Most Gracious as a servant. Verily, He knows each one of them, and has counted them a full counting. And every one of them will come to Him alone on the Day of Resurrection. (19:93-95)

This is why Allah said here,

... وَإِلَى اللَّهِ تُرْجَعُ الأمُورُ

And to Allah return all the matters.

meaning that all matters will be referred to Him on the Day of Resurrection and He will judge His creation as He wills.

Indeed, He is the Most Just, Who never falls into injustice, not even the weight of a speck of dust; if one performs even one good deed, Allah will multiply it up to ten times,

وَيُؤْتِ مِن لَّدُنْهُ أَجْراً عَظِيماً

(and gives from Him a great reward. (4:40)

وَنَضَعُ الْمَوَزِينَ الْقِسْطَ لِيَوْمِ الْقِيَـمَةِ فَلاَ تُظْلَمُ نَفْسٌ شَيْئاً وَإِن كَانَ مِثْقَالَ حَبَّةٍ مِّنْ خَرْدَلٍ أَتَيْنَا بِهَا وَكَفَى بِنَا حَـسِبِينَ

And We shall set up Balances of justice on the Day of Resurrection, then none will be dealt with unjustly in anything. And if there be the weight of a mustard seed, We will bring it. And sufficient are We to take account. (21:47)