Going to the mosque when fasting
Abul-Mutawakkil Al-Nājī reports:
When Abū Hurayrah and his companions fasted, they would sit in the mosque and say, “let us purify our fast.” Hunād b. Al-Sarī, Kitāb Al-Zuhd, article 1207
Hunād b. Al-Sarī, Kitāb Al-Zuhd, article 1207