Muhammad bin Ziyad محمد بن زياد القرشي · The Book of Fasting

'I have sighted the crescent.' He said: 'Do you bear witness that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger?' He said: 'Yes.' So the Prophet gave the call saying: 'Fast."'

"A Bedouin come to the Prophet and said; 'I have sighted the crescent tonight.' He said: 'Do you bear witness that there is none worthy of worship except Allah, and that Messenger?' He said: 'Yes.' He said: 'O Bilal, announce to the people that they should fast tomorrow. "'