'Fast' in the Bible

Why then is this people of Jerusalem slidden back by a perpetual backsliding? they hold fast deceit, they refuse to return.

When they fast, I will not hear their cry; and when they offer burnt-offering and meal-offering, I will not accept them; but I will consume them by the sword, and by the famine, and by the pestilence.

Now it came to pass in the fifth year of Jehoiakim the son of Josiah, king of Judah, in the ninth month, that all the people in Jerusalem, and all the people that came from the cities of Judah unto Jerusalem, proclaimed a fast before Jehovah.

The calamity of Moab is near to come, and his affliction hasteth fast.

Thus saith Jehovah of hosts: The children of Israel and the children of Judah are oppressed together; and all that took them captive hold them fast; they refuse to let them go.