What are the virtues of the months of Rajab and Sha'ban?

The month of Rajab is one of the four sacred months in which Allah has forbidden injustice. It has been narrated in a hadith that there is a command to fast days during the sacred months, but singling out Rajab for fasting a specific day, or for performing night prayers during some of its nights, or celebrating the night of Isra and Mi'raj therein, are innovations that have not been authenticated from the Prophet (peace be upon him) nor his Companions.

As for the month of Sha'ban, it is recommended to increase fasting in it, following the example of the Prophet (peace be upon him), because it is a month in which deeds are raised to the Lord of the Worlds. The Prophet (peace be upon him) fasted more in it than in any other month besides Ramadan. However, singling out the middle of Sha'ban for fasting has no authentic proof.