Maliks Muwatta Book 3, Hadith Number 3.
Section : The Call to Prayer.
Yahya related to me from Malik from Sumayy, the mawla of Abu Bakr ibn Abd ar-Rahman, from Abu Hurayra that the Messenger of Allah, may Allah bless him and grant him peace, said, “If people knew what was in the adhan and the first row of the prayer and could only draw lots for it, they would draw lots. And if they knew what was in doing dhuhr early, they would race each other to it. And if they knew what was in isha and subh, they would go to them even if they had to crawl.”