Ibn Khuzaymah

Sayyiduna Abu Dharr (may Allah be pleased with him) narrates that he said: O Messenger of Allah, the wealthy and affluent people have taken (a lot of) reward and merit. They recite (the Qur’an and other adhkar) as we do, and they also spend (in the way of Allah), but we (the poor) do not spend. The Prophet (peace and blessings be upon him) said: “Shall I not tell you of an action, that when you do it, you will catch up with those who came before you (in reward and merit), and surpass those who come after you, except for the one who does the same as you? After every prayer, recite « سُبْحَانَ اللَٰه » thirty-three times, « الحَمْدُ لِلَٰه » thirty-three times, and « اللهُ أَكْبَرُ » the same number of times. And when you go to your bed (to sleep), recite them in the same way.”