Sahih Muslim Book 4, Hadith 143
The Messenger of Allah (ﷺ) said: If the people were to know what excellence is there in the Adhan and in the first row, and they could not (get these opportunities) except by drawing lots, they would have definitely done that. And if they were to know what excellence lies in joining the prayer in the first takbir (prayer), they would have vied with one another. And if they were to know what excellence lies in the night prayer and morning prayer, they would have definitely come even if crawling (on their knees).
Abu 'Awana reported this hadith with the same chain of transmitters.
The Messenger of Allah (ﷺ) saw (a tendency ) among his Companions to go to the back, so he said to them: Come forward and follow my lead, and let those who come after you follow your lead. People will continue to keep back till Allah will put them at the back.