The Messenger of Allah ﷺ said, "Allah has never sent a prophet nor appointed a successor without there being two types of close companions around him. One group urges him toward good and encourages him in it, while the other urges him toward evil and pushes him toward it. The one truly protected is the one whom Allah protects."
أن رسول الله ﷺ قال: ما بعث الله من نبي ولا استخلف من خليفة إلا كانت له بطانتان: بطانة تأمره بالخير وتحضه عليه، وبطانة تأمر بالسوء وتحضه عليه، والمعصوم من عصم الله.
Bukhari related it in the Book of Qadar (6611) from Abdan, who said, Abdullah informed us, Yunus informed us, from Zuhri, who said, Abu Salama narrated to me, from Abu Saeed Khudri, and he mentioned it. Nasai also related it in his Sunan al-Kubra (8755) through this same route. He also related it (8756) from Abu Salama, from Abu Hurairah, with similar wording. And likewise he related it (8757) from Abu Salama, from Abu Ayub Ansari.So it seems this hadith was known to Abu Salama from three companions, and none of them undermines the others.His statement, "and you believe in the entire Book," means the Book that Allah Almighty revealed to their prophets, such as the Scrolls of Ibrahim, the Torah of Musa, and the Gospel of Isa, whereas they do not believe in the Book that Allah Almighty revealed to the Prophet of Mercy and the last of the prophets, Muhammad bin Abdullah, may Allah's blessings and peace be upon him.