Sahih Muslim Book 4, Hadith Number 776.

Chapter : The reciting of Takbir at the time of bowing and rising in prayer except rising after Ruku’ when it is said: Allah listened to him who praised Him.

It is narrated on the authority of Abu Huraira that he had heard the Messenger of Allah (may peace be upon him) say: He who observed prayer but he did not recite the Umm Al-Qur’an in it, and the rest of the Hadith is the same as transmitted by Sufyan, and in this Hadith the words are: “Allah the Most High said: the prayer is divided into two halves between Me and My servant. The half of it is for Me and the half of it is for My servant.”