Zayd bin Thabit reported,

When the Quranic codices were being compiled, I missed a verse that I used to hear from the Messenger of Allah ﷺ. I found it with Khuzaymah al-Ansari, "Among the believers are men who have been true to their covenant with Allah... and they have not changed in the least" [Ahzab 33:23].Khuzaymah used to be called Dhu al-Shahadatayn, the one with two testimonies, because the Messenger of Allah ﷺ had ruled that his testimony alone counted as the testimony of two men.Zuhri said, "He was killed on the day of Siffin fighting alongside Ali ."

حدثنا عبد الرزاق أنا معمر عن الزهري عن خارجة بن زيد أو غيره أن

زيد بن ثابت قال

لما كتبت المصاحف فقدت آية كنت أسمعها من رسول الله ﷺ فوجدتها عند خزيمة الأنصاري {من المؤمنين رجال صدقوا ما عاهدوا الله عليه إلى تبديلا} قال فكان خزيمة يدعى ذا الشهادتين أجاز رسول الله ﷺ شهادته بشهادة رجلين قال الزهري وقتل يوم صفين مع علي رضي الله عنهما