From Sahih Bukhari (Hadith 2813):
Narrated `Aisha:When Allah's Messenger (ﷺ) returned on the day (of the battle) of Al-Khandaq (i.e. Trench), he put down his arms and took a bath. Then Gabriel whose head was covered with dust, came to him saying, "You have put down your arms! By Allah, I have not put down my arms yet." Allah's Messenger (ﷺ) said, "Where (to go now)?" Gabriel said, "This way," pointing towards the tribe of Bani Quraiza. So Allah's Messenger (ﷺ) went out towards them
Reference: Bukhari 2813