What is the ruling on the one who says: Some of the Companions apostatized, and for this reason Abu Bakr fought them in the Battle of Yamamah?

Question:
May Allah reward you, Honorable Shaykh. This questioner asks: What is the ruling on the one who says that some of the Companions apostatized, and for this reason Abu Bakr and the Muslims fought them in the Battle of Yamamah? And are the people of Yamamah considered among the Companions?

Answer:
They are not all among the Companions. They followed Musaylimah the Liar. Whoever believes in the prophethood of anyone after the sending of the Messenger (peace and blessings be upon him) is a disbeliever and an apostate. Yes, it is possible for one of the Companions to apostatize. Apostasy can happen to one of the Companions or to others. Whoever apostatizes is no longer a Companion; his status as a Companion is invalidated, so he is not a Companion. Those who apostatized with Musaylimah were a small number, and praise be to Allah, they were individuals. Most of them did not become Muslims; most of them did not become Muslims, but rather they followed Musaylimah. Yes.