Abdullah ibn Mas’ud reported: The Messenger of Allah, peace and blessings be upon him, said, “Whoever focuses on only one concern, the afterlife, Allah will be enough for his concerns in the world. Whoever scatters his concerns among the matters of the world, it does not matter to Allah in which valley he meets his demise.”
Source: Sunan Ibn Mājah 4106
Grade: Hasan (fair) according to Al-Albani
عَنْ عَبْدِ اللَّهِ قَالَ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ مَنْ جَعَلَ الْهُمُومَ هَمًّا وَاحِدًا هَمَّ الْمَعَادِ كَفَاهُ اللَّهُ هَمَّ دُنْيَاهُ وَمَنْ تَشَعَّبَتْ بِهِ الْهُمُومُ فِي أَحْوَالِ الدُّنْيَا لَمْ يُبَالِ اللَّهُ فِي أَيِّ أَوْدِيَتِهِ هَلَكَ
4106 سنن ابن ماجه كتاب الزهد باب الهم بالدنيا
3330 المحدث الألباني خلاصة حكم المحدث حسن في صحيح ابن ماجه