Musannaf Ibn Abi Shayba 28:552

Ya'la ibn 'Ubayd narrated to us, he said: Abu Hayyan narrated to us, from a sheikh from the people of Medina, who said: There was a friendship and acquaintance between me and the scribe of 'Abdullah. So I wrote to him to copy for me the letter of 'Abdullah ibn Abi Awfa. He said: The Messenger of Allah (ﷺ) said: "Do not ask to meet the enemy, and if you meet them, then be patient, and know that Paradise is under the shadows of the swords." And he used to wait; so when the sun passed the meridian, he would advance toward his enemy.