The Messenger of Allah ﷺ said, "No servant truly believes until he believes in four things, that he testifies there is no god but Allah and that I am Muhammad, the Messenger of Allah, whom He sent with the truth, and that he believes in death, and in the resurrection after death, and that he believes in the divine decree."Mahmud bin Ghaylan narrated to us, Nadr bin Shumayl narrated to us, from Shuba, something similar, except that he said Rubai reported it from a man, from Ali.
حدثنا محمود بن غيلان حدثنا أبو داود قال أنبأنا شعبة عن منصور عن ربعي بن حراش
قال رسول الله ﷺ لا يؤمن عبد حتى يؤمن بأربع يشهد أن لا إله إلا الله وأني محمد رسول الله بعثني بالحق ويؤمن بالموت وبالبعث بعد الموت ويؤمن بالقدر حدثنا محمود بن غيلان حدثنا النضر بن شميل عن شعبة نحوه إلا أنه قال ربعي عن رجل عن علي
[Hasan]Ibn Majah also narrated it in the introduction, chapter on divine decree, hadith 81, from the hadith of Mansur.It is also found in the Musnad of Abu Dawud Tayalisi, hadith 106.Ibn Hibban graded it sahih (al-Ihsan): 178, as did Hakim: 1/33, through this same route, and Dhahabi and others agreed.The hadith has very many corroborating narrations.The report from Waki is sahih from him.