the view of those who regard it as forgoing what is preferable or as disliked—and this is the correct view.
The authentic hadiths from the Prophet (peace and blessings be upon him), such as his prohibition of this practice to 'Abd Allāh ibn 'Amr and his statement,
“Whoever fasts year-round has neither fasted nor broken his fast,”
and other reports clearly indicate that this practice is not prescribed.
Anyone who interprets this as referring to fasting on the five prohibited days is mistaken. Fasting year-round does not mean fasting only five days. Moreover, fasting on those five days is forbidden even if one does not fast on any other days. Thus, fasting on them was not prohibited because it constituted year-round fasting. Nor can a prohibition against fasting for more than three hundred days be understood as referring to just five. This would be like someone saying, “Bring me everyone in the congregational mosque,” while meaning only five of them.
Furthermore, he explained that doing so causes the eyes to become sunken and leaves a person exhausted. This results from fasting continuously, not from fasting on those five days.
An authentic report also relates:
“A man asked him about fasting year-round. He replied, ‘Whoever fasts year-round has neither fasted nor broken his fast.’
“The man asked, ‘What about someone who fasts for two days and does not fast for one day?’ He replied, ‘Who could manage that?’
“He asked, ‘What about someone who fasts for one day and does not fast for two days?’ He replied, ‘I wish I had been given the strength to do that.’
“He then asked, ‘What about someone who fasts one day and does not fast the next?’ He replied, ‘That is the best form of fasting.’”
Thus, they asked him about fasting all the time, then two-thirds of the time, then one-third, and then half.