1. It was narrated from ‘Ubaadah ibn as-Saamit that the Prophet (saw) said: “Whoever turns over at night and says
Laa ilaaha ill-Allaah wahdahu laa shareeka lah, lahu’l-mulk wa lahu’l-hamd wa huwa ‘ala kulli shay’in qadeer. Al-hamdu-lillaah wa subhaan-Allaah wa laa ilaaha ill-Allaah wa Allaahu akbar, wa laa hawla wa laa quwwata illa Billaah
(There is no god but Allaah Alone, with no partner or associate. To Him belongs praise and His is the sovereignty, and He is Able to do all things. Praise be to Allaah, glory be to Allaah, there is no god but Allaah and Allaah is Most Great. There is no power and no strength except with Allaah),
then he says,
Allaahumma aghfir li (O Allaah, forgive me),
or he offers supplication, his supplication will be answered.
If he does wudoo’ and prays, his prayer (salaah) will be accepted.”
Narrated by al-Bukhaari (1154).
2.It was narrated that Ibn 'Abbas said:
"When the Prophet (ﷺ) got up at night to pray Tahajjud, he said:
Allahumma, lakal-hamdu anta nurus-samawati wal-ardi wa man fihinna wa lakal-hamdu anta qayyamus-samawati wal ardi wa man fihinna wa lakal-hamdu, anta haqqun wa wa'duka haqqun wal jannatu haqqun wan-nuru haqqun wan-nabiyyuna haqqun wa Muhammadan haqqun, laka aslant wa 'alaika tawakkaltu wa bika amant.
( O Allah, to You be praise, You are the Light of the heavens and earth and whoever is in them. To You be praise, You are the Sustainer of the Heavens and the earth and whoever is in them. To You be praise, You are the Sovereign of the heavens and earth and whoever is in them. To You be praise; You are True, Your promise is true, Paradise is true, Hell is true, the Hour is true, the Prophets are true and Muhammad is true. To You have I submitted, in You I put my trust and in You I have believed.'
" Then (one of the narrators) Qutaibah mentioned some words the meaning of which was:
"Wa bika khasamtu wa ilaika hakamtu, ighfirli ma quadrate wa ma akhkhartu wa ma a'lantu antal-muqaddimu wa antal-mu'khkhir, la ilaha illa anta wa la hawla wa la quwwata illa billah
(And with Your help I argue [with my opponents, the non-believers], and I take You as a judge [to judge between us]. Forgive me my past and future sins and those that I commit openly. You are the One who puts [some people] back and bring [others] forward. There is no God but You and there is no power and no strength except with Allah).'"
Sahih (Darussalam) Sunan an-Nasa'i 1619