not to fast.

It is preferable, however, to fast beginning at dawn. It is known that if a person knew the time when dawn might break, he would be permitted either to abstain or to eat, even if he abstained at dawn. For there is no basis for regarding abstention as recommended, but … (1).

Most of Ahmad’s recorded statements support precisely this view: he recommended fasting that day and fasted it himself, but did not consider it obligatory. In this, he relied on reports from the Companions recorded in the collections of legal questions transmitted by his son ʿAbd Allāh, al-Fadl ibn Ziyād al-Qattān and others. He followed what was reported from ʿAbd Allāh ibn ʿUmar and others like him.

What is reported from them is that they would fast when the sky was overcast, without considering fasting obligatory. Most people did not fast, and they did not censure them for refraining.

He did not recommend fasting when the sky was clear; rather, he prohibited it. This is because both the presumption and the apparent circumstances indicate that the crescent has not appeared. Fasting that day would therefore mean beginning Ramadan a day early, which the Prophet, peace and blessings be upon him, prohibited.

Two different positions are reported from him on whether a day of overcast skies is called a “day of doubt.” His followers likewise differed on this matter.