Musnad Ahmad 658:239

Waki' narrated to us, he said: Mis'ar narrated to us, from Thabit ibn 'Ubayd, from Ibn al-Bara', from al-Bara' who said: When we used to pray with the Messenger of Allah, may Allah bless him and grant him peace, it was among what he liked—or what we liked—that we would stand to his right. I heard him say: "My Lord, protect me from Your punishment on the day You gather Your servants—or [on the day] You resurrect Your servants."