Is it true that the narrators of Hadith to whom the chains of narration (Isnad) can be traced back are only seven (Abu Hurairah, Abdullah ibn Umar, Anas ibn Malik, Aisha, Abdullah ibn Abbas, Jabir ibn Abdullah, and Abu Sa'id al-Khudri), and that every Hadith's chain of narration ends with one of these seven?

The notion that narrating hadith was limited to seven Companions is incorrect. Rather, a large number of Companions narrated hadith. These seven are among the Companions who narrated the most hadith, and it is not that narration was restricted to them.

Imam Ahmad mentioned that six of the Companions narrated extensively and lived long lives: Abu Hurayrah, Ibn Umar, Aisha, Jabir ibn Abdullah, Ibn Abbas, and Anas. Abu Hurayrah narrated the most among them.

Shaykh Muhammad Abu Shahbah mentioned that seven Companions narrated the most, namely: Abu Hurayrah, Abdullah ibn Umar, Anas ibn Malik, Aisha, Ibn Abbas, Jabir ibn Abdullah, and Abu Sa'id al-Khudri.

Scholars have relied on what Abu al-Faraj ibn al-Jawzi stated in his book "Talqih Fuhum Ahl al-Athar" concerning this, based on what was attributed to each Companion in the Musnad of Baqi ibn Makhlad al-Andalusi.