Musannaf Ibn Abi Shayba 34:266

Aswad narrated to us, Ja'far ibn Ziyad narrated to us, from Hisham ibn Hassan, from Ibn Sirin, who said: The first person to ask for evidence (al-bayyinah) was Shurayh. So they said, "O Abu Umayyah, you have introduced a new practice (ahdath-ta)!" He said, "You introduced new practices (ahdath-tum), so I introduced a new practice (fa-ahdath-tu)."