It's the Hebrew month of Av. It is the fifth month of the Biblical calendar (five months after Nissan), and only two months before the High Holiday season.
Of course, “Av” literally means “father”. This month commemorates some of the saddest days in Jewish history. Both of the Temples were destroyed during this month. It is also on the 9th of Av that the 12 spies scoped out the Promised Land, but ten of them brought back a negative report — leading to the Hebrews being forced to return. Еще