the Iqamah was pronounced (for the night prayer) and the Messenger of Allah (ﷺ) remained engaged in talking (to a person) in the corner of the mosque. He did not begin prayer until the people slept.
Sunan Abi Dawud Book 2, Hadith 154
← Previous Hadith we stood for praying at Mina when the Imam had not come out. Some of us sat down (and I too). An old man from Kufah said to me: Why did you down? I said : Ibn Buraidah, this is Sumud (i.e., waiting for the Imam in the standing condition). The old man then narrated a tradition from ‘Abd al-Rahman b. ‘Awaajah on the authority of al-Bara’ b. ‘Azib: We would stand in rows during the time of the Messenger of Allah (ﷺ) for a long time before he pronounced Takbir. He further said; Allah, the Exalted and Mighty, sends blessings and the angles invoke blessings for those who are nearer to the front rows. No step is more liking to Allah than a step which one takes to join the row (of the prayer).

Sunan Abi Dawud Book 2, Hadith 153 Next Hadith → when the Iqamah was pronounced and the Messenger of Allah (ﷺ) saw that they (the people) were small in number, he would sit down, nd would not pray; but when he saw them (the people) large in number, he would pray.

Sunan Abi Dawud Book 2, Hadith 155