Muslim narrated in his Sahih on the authority of Kurayb that Umm al-Fadl bint al-Harith sent him to Muawiyah in the Levant. He said, “So I came to the Levant and fulfilled her need. Ramadan began and I was in the Levant and saw the crescent on Friday night. Then I came to Medina at the end of the month, so Abdullah bin Abbas asked me, then he mentioned the crescent.” He said, “When did you see the crescent?” I said, “We saw it on Friday night.” He said, “You saw it,” so I said, “Yes,” and the people saw it and fasted, and Muawiyah fasted. He said, “But we saw it on Saturday night. So we will continue to fast until we complete thirty days or we see it.” So I said, “Are you not satisfied with Muawiyah’s sighting and fasting ?” He said, “No.” This is how the Messenger of God, may God bless him and grant him peace, commanded us. p>

And peace be upon him