Sunan Abi Dawud 1289
سنن أبي داود#1289SahihNarrated Nu'aym ibn Hammar: I heard the Messenger of Allah (ﷺ) say: Allah, the Exalted, says: Son of Adam, do not be helpless in performing four rak'ahs for Me at the beginning of the day: I will supply what you need till the end of it
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Muhyi Al-Din Abdul HamidSahih
Zubair Ali ZaiSahih
In-book reference: 5:40