Allah (سبحانه وتعالى) says in a verse of the Holy Qur'an:

مَا أَصَابَ مِنْ مُصِيبَةٍ فِي الْأَرْضِ وَلَا فِي أَنْفُسِكُمْ

إِلَّا فِي كِتَابٍ مِنْ قَبْلِ أَنْ نَبْرَأَهَا ۚ إِنَّ ذَٰلِكَ عَلَى اللَّهِ يَسِيرٌ

"No calamity befalls on the earth or in yourselves but is inscribed in the Book of Decrees (Al-Lauh Al-Mahfuz), before We bring it into existence. Verily, that is easy for Allah." (57:22)

A person should never object to the Decree of Allah سبحانه وتعالى but be content with it in all circumstances. We should realise that Allah سبحانه وتعالى is the All-Knowing and All-Wise and whatever He decrees is best for us although we may not understand it.

[This short excerpt is based on a brothers' majlis (gathering for spiritual training) held by Shaykh Abu Yusuf Riyadh ul Haq on 3rd May 2000]