Sunan Abi Dawud 1529
سنن أبي داود#1529SahihAbu Sa'id al-Khudri reported the Messenger of Allah (ﷺ) as saying:If anyone says "I am pleased with Allah as Lord, with Islam as religion and with Muhammad (ﷺ) as Apostle" Paradise will be his due
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
Shuaib Al ArnautSahih
Zubair Ali ZaiIsnaad Sahih
In-book reference: 8:114