Aslamualaakum. I heard somone say that Anas said he used to go and hear the hadith from the messenger of Allah then he would go and review it with other sahabah. Is this authentic and is it in Bukhari.

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

The Hadeeth which you referred to in the question is not in Saheeh Al-Bukhari but was mentioned in Al-Jaami‘ li Akhlaaq Ar-Raawi wa Aadaab As-Saami‘ (Proper conduct of Hadeeth narrators) by Al-Khateeb Al-Baghdaadi. He recorded it with its chain of narrators under the title: “Students revising the Hadeeth after having memorized it so that it is firm in their memory.” He said, Anas ibn Maalik said: “We used to be with the Prophet and would hear his words, and when we left, we would revise it among ourselves until we memorized it.”

However, we have not found whether it has been determined authentic or weak by any scholar.

Al-Khateeb mentioned many Ahadeeth along with the above which urge revising and memorizing Ahaadeeth, and they were related by ‘Ali and other companions all.

As-Sakhaawi said in Fat-h Al-Mugheeth:

“Revising helps you to make what you have learned firm in your memory, and it is one of the most effective means to benefit from it. The evidence for this is that Jibreel (Gabriel) revised the Quran with the Prophet every Ramadan.”

Allaah Knows best.