Issues:
First: If an upright person looks for the crescent along with a large group, and he has strong eyesight but no one else sees it, should the fast begin on the basis of his sighting?
The answer: Yes, the fast begins on the basis of his sighting. This is the well-known position in our school, and it is the view of most scholars. Some scholars, however, held that if no one else sees it despite the large gathering, his statement is not to be considered, since it is unlikely that he alone would see it while they did not.
The correct view is the first one, due to his uprightness and trustworthiness.
Second: Whoever sees the crescent while being someone who commits a major sin, such as drinking wine, must report that he saw the crescent, but he need not disclose that he commits a major sin, because legal rulings may be treated separately.
Third: According to the school, the testimony of a person whose condition is outwardly unknown is not accepted, because his uprightness is unknown.
In my view, if the judge trusts his statement, there is no need to investigate his uprightness.
His statement: “even if she is a woman.” The word “even if” generally indicates the existence of a differing view, and that is the case here. Some scholars held that a woman’s testimony is not accepted, neither for Ramadan nor for any other month, because the one who sighted the crescent during the time of the Messenger of Allah, peace and blessings be upon him, was a man (1); and because the Prophet, peace and blessings be upon him, said: “If two witnesses testify, then fast and end the fast” (2). A woman is a witness, but not a male witness.