Jami` at-Tirmidhi Hadith 3414

The Messenger of Allah (ﷺ) said: “Whoever wakes up in the night and says, ‘None has the right to be worshiped but Allah, alone, without partner, to Him belongs the Dominion, and to Him is the praise, and He has power over all things. And Glory is to Allah, and all the praise is to Allah, and ‘None has the right to be worshiped but Allah, and Allah is the greatest, and there is no might nor power except by Allah (Lā ilāha illallāh, waḥdahu lā sharīka lahu, lahul-mulku wa lahul-ḥamdu, wa huwa `alā kulli shai'in qadīr. Wa subḥān Allah, walḥamdulillāh, wa lā ilāha illallāh, wa Allāhu akbar, wa lā ḥawla wa lā quwwata illā billāh.)’ – then he said: ‘O my Lord, forgive me (Rabbighfirlī)’ – or he said – ‘then he supplicates, he shall be responded to. So he makes a firm determination, then performs Wudu', then he performs Salat, his Salat shall be accepted.”