They have been mentioned in a book titled “Kanz al-Maram fir A’amal Shahr al-Siyam”.
Also, Imam Baqer (AS) said: Anyone who fasts in the days of Ramadan and spends part of the night in worshiping, keeps his stomach and his lust at bay, controls his eyes and tongue, and avoids harming other people, he will get out of sins and gets as pure as he was on the day he was born.
We read in part of the book: Always remember the Day of Judgment, make provision for the time you meet God, and always remain humble and serene. When you are fasting, with a soul devoid of sins and impurities, put yourself in God’s hands and do as He has commanded. If you do all of these fully, you are truly fasting and have obeyed His command. And if you do some of these partially, your fasting will be proportionately deficient.
The Holy Prophet (PBUH) saw a woman who was fasting but used foul language. He ordered that she be served food. She said: ‘But I am fasting, Oh Messenger of God!’ “The holy Prophet said: How can you be fasting when you use foul language?
And Imam Ali (AS) said: Many persons get nothing out of their fasts but hunger and thirst, many more get nothing out of their night prayers but exertions and sleepless nights. Wise and sagacious persons are praiseworthy even if they do not fast and sleep during the nights.