Abu Sa’id al-Khudri reported Allah’s Messenger (peace be upon him) as saying:
The inmates of Paradise would see the inmates of the apartment over them just as you see the shining planets which remain in the eastern and the western horizon because of the superiority some have over others. They said: Allah’s Messenger, would in these abodes of Apostles others besides them not be able to reach? He said: Yes, they will, by Him, in Whose hand is my life, those who believe in God and acknowledge the Truth, will reach them.
(Muslim Book 40, Hadith 6790)