question #2 Sahih Muslim 221b, Book 1, Hadith 436 : How does belief in monotheism relate to the eligibility for entering Paradise in Islam?

We, about forty men, were with the Messenger of Allah (ﷺ) in a camp when he said: Aren’t you pleased that they should constitute one-fourth of the inhabitants of Paradise? He (the narrator) said: Yes. He (the Holy Prophet) again said: Aren’t you pleased that you should constitute one-third of the inhabitants of Paradise? They said: Yes. Upon this he again said: By Him in Whose Hand is my life, I hope that you would constitute one-half of the inhabitants of Paradise and the reason is that no one would be admitted into Paradise but a believer and you are no more among the polytheists than as a white hair on the skin of a black ox or a black hair on the skin of a red ox.