It is narrated from Sayyiduna Ibn Abbas (may Allah be pleased with them both) that the Prophet (peace and blessings be upon him) did not observe complete fasting in any month except the month of Ramadan. However, sometimes he would fast with such continuity that people would say that now the Prophet (peace and blessings be upon him) will not leave any fast, and sometimes he would break his fasts with such continuity that people would say that now the Prophet (peace and blessings be upon him) will not fast anymore.