Sahih al-Bukhari 598

Musaddad narrated to us: Yahya narrated to us, from Hisham, who said: Yahya—meaning Ibn Abi Kathir—narrated to us, from Abu Salama, from Jabir, who said: On the day of the Trench, ‘Umar began cursing the disbelievers and said, ‘I could hardly pray the afternoon prayer before the sun set.’ He said: We went down to Buthan, and he prayed after sunset, then prayed the sunset prayer.