Questioner:

Does a person who doubts the beginning of Ramaḍān, fast a couple of days before it?

Shaykh Muqbil ibn Hādī al-Wādi’ī:

There are some from the Hanbalites who say this, however the correct opinion is that he should not fast since it has been authenticated that the Prophet ﷺ  said, Do not anticipate Ramaḍān by fasting one or two days before it begins”. It has also been reported on the authority of ʿAmmār bin Yāsir who said, “He who observes the fast on a doubtful day, has in fact disobeyed Abūl-Qāsim [meaning the Prophet ﷺ]”. So the correct opinion is that he should not fast.

The Prophet ﷺ said “Fast when you see the new moon and break your fast when you see the new moon, and if you are not sure, then complete the number of Shaʿbān as thirty days.” There isn’t anything [to be followed] after these clarifications.