Tafseer: Surah Tur Verse 4
al Baitul Ma’mur is the Ka’bah in the sky meant for the angels’ service and is parallel to the Ka’bah on earth. According to a hadith in Sahihain the Holy Prophet (SallAllahu alaihi wa Sallam) said about his ascension to the seventh heaven: “Then, I was taken to al Baitul Ma’mur. It is visited every day by seventy thousand angels who will not come back to visit it again ” because every day other new angels take their turn to visit it. (Ibn Kathir)
al Baitul Ma’mur is the Ka’bah of the angels who reside in the seventh heaven. When the Holy Prophet SallAllahu alaihi wa Sallam reached the seventh heaven on the Night of Mi’raaj, he saw Nabi Ibrahim (alaihis salaam) reclining with his back on al Baitul Ma’mur. It was Nabi Ibrahim (alaihis salaam) who built the Ka’bah on earth, and thus the reward is linked with his action in that Allah Ta’ala has blessed him with a special connection with al Baitul Ma’mur (Ibn Kathir)
Source: Ma’ariful Qur’aan – Mufti Muhammad Shafi Usmani