وَلِيُمَحِّصَ اللَّهُ الَّذِينَ آمَنُوا وَيَمْحَقَ الْكَافِرِينَ ١٤١
Allah's object also is to purge those that are true in Faith and to deprive of blessing Those that resist Faith.
3:142
أَمْ حَسِبْتُمْ أَنْ تَدْخُلُوا الْجَنَّةَ وَلَمَّا يَعْلَمِ اللَّهُ الَّذِينَ جَاهَدُوا مِنْكُمْ وَيَعْلَمَ الصَّابِرِينَ ١٤٢
Did ye think that ye would enter Heaven without Allah testing those of you who fought hard (In His Cause) and remained steadfast?
3:143
وَلَقَدْ كُنْتُمْ تَمَنَّوْنَ الْمَوْتَ مِنْ قَبْلِ أَنْ تَلْقَوْهُ فَقَدْ رَأَيْتُمُوهُ وَأَنْتُمْ تَنْظُرُونَ ١٤٣
Ye did indeed wish for death before ye met him: Now ye have seen him with your own eyes, (And ye flinch!)
3:144
وَمَا مُحَمَّدٌ إِلَّا رَسُولٌ قَدْ خَلَتْ مِنْ قَبْلِهِ الرُّسُلُ ۚ أَفَإِنْ مَاتَ أَوْ قُتِلَ انْقَلَبْتُمْ عَلَىٰ أَعْقَابِكُمْ ۚ وَمَنْ يَنْقَلِبْ عَلَىٰ عَقِبَيْهِ فَلَنْ يَضُرَّ اللَّهَ شَيْئًا ۗ وَسَيَجْزِي اللَّهُ الشَّاكِرِينَ ١٤٤
Muhammad is no more than a messenger: many Were the messenger that passed away before him. If he died or were slain, will ye then Turn back on your heels? If any did turn back on his heels, not the least harm will he do to Allah; but Allah (on the other hand) will swiftly reward those who (serve Him) with gratitude.
3:145
وَمَا كَانَ لِنَفْسٍ أَنْ تَمُوتَ إِلَّا بِإِذْنِ اللَّهِ كِتَابًا مُؤَجَّلًا ۗ وَمَنْ يُرِدْ ثَوَابَ الدُّنْيَا نُؤْتِهِ مِنْهَا وَمَنْ يُرِدْ ثَوَابَ الْآخِرَةِ نُؤْتِهِ مِنْهَا ۚ وَسَنَجْزِي الشَّاكِرِينَ ١٤٥
Nor can a soul die except by Allah's leave, the term being fixed as by writing. If any do desire a reward in this life, We shall give it to him; and if any do desire a reward in the Hereafter, We shall give it to him. And swiftly shall We reward those that (serve us with) gratitude.