Zayd bin Yahya bin 'Ubaid زيد بن يحيى بن عبيد · The Book of the Sunnah

"The Messenger of Allah (ﷺ) said: 'I have been commanded to fight the people until they testify to La ilaha ill-allah (none has the right to be worshipped but Allah) and that I am the Messenger of Allah, and establish regular prayers and pay Zakat.'"