رَبِّ السَّمَاوَاتِ وَالاَْرْضِ وَمَا بَيْنَهُمَا(As) a mercy from your Lord. Verily, He is the All-Hearer, the All-Knower. The Lord of the heavens and the earth and all that is between them,means, the One Who sent down the Qur'an is the Lord, Creator and Sovereign of the heavens and the earth and everything in between them.إِن كُنتُم مُّوقِنِينَif you (but) have a faith with certainty.Then Allah says:لَاا إِلَهَ إِلاَّ هُوَ يُحْيِي وَيُمِيتُ رَبُّكُمْ وَرَبُّ ابَايِكُمُ الاْاَوَّلِينَ