Sayyiduna Anas bin Malik (may Allah be pleased with him) said: I began serving the Messenger of Allah (peace and blessings be upon him) when I was eight years old. (The narrator) Yazid said: Hammad bin Salamah guided me to this shaykh (Abu Muhammad al-Thaqafi).
Hadith Referenceالمعجم الكبير للطبراني / باب الألف / 709