Narrated Ubaydullah: Harb ibn Ubaydullah told on the authority of his grandfather, his mother's father, that he had it on the authority of his father that the Messenger of Allah ﷺ said: Tithes are to be levied on Jews and Christians, but not on Muslims.

The tradition mentioned above has also been transmitted by Harb bin Ubaid Allah from the Prophet ﷺ to the same effect through a different chain of narrators. This version has the word kharaj (land tax) instead of ‘ushr (tithes).

Narrated A man of Banu Taghlib: Harb ibn Ubaydullah ibn Umayr ath-Thaqafi told on the authority of his grandfather, a man of Banu Taghlib: I came to the Prophet ﷺ, embraced Islam, and he taught me Islam. He also taught me how I should take sadaqah from my people who had become Muslim. I then returned to him and said: Messenger of Allah, I remembered whatever you taught me except the sadaqah. Should I levy tithe on them? He replied: No, tithes are to be levied on Christians and Jews.