Ibn Umar reported: A man came to the Prophet, peace and blessings be upon him, and he said, “O Messenger of Allah, give me a teaching and make it concise.” The Prophet said, “Pray your prayers as if they were your last, for if you do not see Him, He surely sees you. Give up trying to acquire what people have and you will be wealthy. Beware of doing anything for which you must apologize.”
Source: al-Mu’jam al-Awsaṭ 4427
Grade: Sahih (authentic) according to Al-Albani
عَنْ ابْنَ عُمَر قَالَ أَتَى رَجُلٌ النَّبِيَّ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ فَقَالَ يَا رَسُولَ اللَّهِ حَدِّثْنِي بِحَدِيثٍ وَاجْعَلْهُ مُوجَزًا فَقَالَ لَهُ النَّبِيُّ صَلَّى اللهُ عَلَيْهِ وَسَلَّمَ صَلِّ صَلَاةَ مُوَدِّعٍ فَإِنَّكَ إِنْ كُنْتَ لَا تَرَاهُ فَإِنَّهُ يَرَاكَ وَأْيَسْ مِمَّا فِي أَيْدِي النَّاسِ تَكُنْ غَنِيًّا وَإِيَّاكَ وَمَا يُعْتَذَرُ مِنْهُ
4427 المعجم الأوسط
3776 المحدث الألباني خلاصة حكم المحدث صحيح في صحيح الجامع