Abu Sa'id Al-Khudri and Abu Hurairah (May Allah be pleased with them) reported:
The Messenger of Allah (ﷺ) said, "If a person says: 'La ilaha illallahu wallahu Akbar (There is no true god except Allah and Allah is Greatest)', his Rubb responds to him and affirms: '(Yes!) There is no true god except I, and I am the Greatest.' When he says: 'La ilaha illallahu Wahdahu la sharika Lahu (There is no true god except Allah, the One, He has no partner).' Allah (SWT) affirms: '(Yes!) There is no true god except I. I have no partner.' When he says: 'La ilaha illallahu Lahul mulku wa Lahul-hamdu (the sovereignty belongs to Him and all the praise is due to Him).' He (SWT) affirms: '(Yes!) There is no true god except I, Mine is the praise and to Me belongs the sovereignty.' When he says: 'La ilaha illallahu wa la hawla wa la quwwata illa Billah (There is no true god except Allah, and there is no might and power but with Allah).' He (SWT) affirms: '(Yes!) There is no true god except I, and there is no might and power but with Me."' The Messenger of Allah (ﷺ) added, "He who recites this during his illness and dies, will not be touched by the Fire (Hell)."[At-Tirmidhi].
App reference: Book 7, Hadith 16
Arabic/English book reference: Book 7, Hadith 909