Al-Matalib al-'Aliyah 3403 — Remembrance in the morning and evening

It is narrated from Sayyiduna Salman al-Farisi (may Allah be pleased with him) that he said: "When a servant of Allah recites this du'a in the morning: 'Allahumma anta rabbi la sharika lak, wa asbahtu wa asbaha al-mulku lillah, la sharika lah' (O Allah, You are my Lord, You have no partner; I have reached the morning, and the whole universe and dominion have reached the morning for Allah, who has no partner), then whenever a servant says these words in the morning and the evening, Allah Almighty expiates for him all the sins he committed in the interval between these two times; or the narrator said, with doubt, these words: the sins he incurred between them."
Imam Musaddad transmitted this narration in his Musnad. One narrator in its chain (a man from al-Nakha') is unknown or unidentified; however, in its meaning it agrees with other reliable adhkar.