حَدَّثَنَا مُحَمَّدُ بْنُ رُمْحٍ، أَنْبَأَنَا اللَّيْثُ بْنُ سَعْدٍ، عَنْ يَزِيدَ بْنِ أَبِي حَبِيبٍ، عَنْ سَعْدِ بْنِ سِنَانٍ، عَنْ أَنَسِ بْنِ مَالِكٍ، عَنْ رَسُولِ اللَّهِ ـ صلى الله عليه وسلم ـ أَنَّهُ قَالَ ‏ "‏ عِظَمُ الْجَزَاءِ مَعَ عِظَمِ الْبَلاَءِ وَإِنَّ اللَّهَ إِذَا أَحَبَّ قَوْمًا ابْتَلاَهُمْ فَمَنْ رَضِيَ فَلَهُ الرِّضَا وَمَنْ سَخِطَ فَلَهُ السُّخْطُ ‏"‏ ‏.‏

It was narrated from Anas bin Malik that the Messenger of Allah (ﷺ) said: “The greatest reward comes with the greatest trial. When Allah loves a people He tests them. Whoever accepts that wins His pleasure but whoever is discontent with that earns His wrath.”

Sunan Ibn Majah 4031
Grade: Hasan (Darussalam)
https://sunnah.com/ibnmajah:4031