Musnad Ahmad 4317

It was narrated from ‘Abdur-Rahman bin al-Aswad that his father said: ‘Alqamah and I entered upon ’Abdullah bin Masood at midday when it was very hot. When the sun passed the meridian he gave the iqamah for prayer and we stood behind him. He took hold of my hand and my companion's hand and made each of us stand on either side of him, and he stood between us. Then he said: This is what the Messenger of Allah (ﷺ) used to do if they were three. Then he led us in prayer and when he finished he said: There will be rulers who will delay the prayer from its proper time. Do not wait for them, rather (pray on time and) make your prayer with them nafl.