Musnad Ahmad 30:1751

Ishaq ibn Isa narrated to us, Malik informed us, from Sumayy, from Abu Salih, from Abu Hurairah, that the Messenger of Allah (peace and blessings of Allah be upon him) said: "If the people knew what is in the call (to prayer) and the first row, and then they could find no other way but to draw lots for it, they would draw lots for it. And if they knew what is in coming early (to the prayer), they would race toward it. And if they knew what is in the night prayer (Isha) and the dawn prayer (Fajr), they would come to them even if they had to crawl."