'Seventh' in the Bible

"Talk to everyone in the land, as well as to the priests. Ask them, "When you were fasting and mourning during the fifth and seventh months for the past seventy years, were you really fasting for me?

"This is what the LORD of the Heavenly Armies says: "The fasts that occur in the fourth, fifth, seventh, and tenth months will be joyful and glad times for the house of Judah, replete with cheerful festivals. Therefore, love truth and peace.'"