From Sahih Bukhari (Hadith 7201):
Narrated Anas:The Prophet (ﷺ) went out on a cold morning while the Muhajirin (emigrants) and the Ansar were digging the trench. The Prophet (ﷺ) then said, "O Allah! The real goodness is the goodness of the Here after, so please forgive the Ansar and the Muhajirin." They replied, "We are those who have given the Pledge of allegiance to Muhammad for to observe Jihad as long as we remain alive
Reference: Bukhari 7201