The four compilers of the Sunan all relate this report through various chains that go back to al-Aʿmash, from Abū Wāʾil, from Masrūq, from Muʿādh.
Aḥmad also said: “Muʿāwiyah ibn ʿAmr and Hārūn ibn Maʿrūf both narrated to us: ʿAbd Allāh ibn Wahb narrated to us, from Ḥaywah, from Yazīd ibn Abī Ḥabīb, from Salamah ibn Usāmah, from Yaḥyā ibn al-Ḥakam, that Muʿādh said:
‘The Messenger of Allah ﷺ sent me to collect zakāt from the people of Yemen. He instructed me to take from cattle one year-old calf (tabīʿ) for every thirty head’—Hārūn explained, ‘A tabīʿ is a male or female yearling’—‘and a two-year-old cow (musinnah) for every forty. The people then suggested that I take something for the intervals between forty and fifty, between sixty and seventy, and between eighty and ninety, but I refused and told them that I would first consult the Messenger of Allah ﷺ. When I returned I informed him, and he ordered me as follows: for every thirty, one tabīʿ; for every forty, one musinnah; for sixty, two tabīʿs; for seventy, one musinnah and one tabīʿ; for eighty, two musinnahs; for ninety, three tabīʿs; for one hundred, one musinnah and two tabīʿs; for one hundred and ten, two musinnahs and one tabīʿ; and for one hundred and twenty, either three musinnahs or four tabīʿs.
He further commanded me not to take anything for the intermediate numbers unless they reach the value of a musinnah or a two-year-old beast, affirming that no zakāt is due on the awqāṣ—that is, the numbers that fall between the fixed thresholds.’
This narration is unique to Aḥmad. It would appear from it that Muʿādh returned from Yemen to see the Messenger of Allah ﷺ, whereas the sound position, mentioned earlier, is that he did not meet him again after being dispatched.
ʿAbd al-Razzāq said: Maʿmar narrated to us, from al-Zuhrī, from Ubayy ibn Kaʿb ibn Mālik, who said: ‘Muʿādh ibn Jabal was a handsome and magnanimous young man, among the finest of his people. He never refused anyone who asked him for something, until heavy debts accumulated against him…’