Aal-'Imran - 3:142

أَمْ حَسِبْتُمْ أَن تَدْخُلُواْ الْجَنَّةَ وَلَمَّا يَعْلَمِ اللّهُ الَّذِينَ جَاهَدُواْ مِنكُمْ وَيَعْلَمَ الصَّابِرِينَ
[3:142]
Do you think that you will enter the garden while Allah has not yet known those who strive hard from among you, and (He has not) known the patient.
Did ye think that ye would enter Heaven without Allah testing those of you who fought hard (In His Cause) and remained steadfast?
Or deemed ye that ye would enter paradise while yet Allah knoweth not those of you who really strive, nor knoweth those (of you) who are steadfast?