Hazrat Usman bin Hakeem says that I asked Hazrat Saeed bin Jubair about fasting in the month of Rajab. He replied that I heard Hazrat Abdullah bin Abbas say that the Holy Prophet (peace and blessings be upon him) would sometimes fast continuously to such an extent that we would feel he would never stop fasting, and at other times he would leave off fasting to such an extent that we would feel he would not fast.