'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 an oblation, I will not accept them: but I will consume them by the sword, and by the famine, and by the pestilence.

You go and read the words of the LORD that you wrote at my dictation from the scroll. Read them to the people at the LORD's Temple on the fast day. Also read them to all the people of Judah who are coming from their towns.

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

Declare ye in Egypt, and publish in Migdol, and publish in Noph and in Tahpanhes: say ye, Stand fast, and prepare thee; for the sword shall devour round about thee.

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

Thus saith the LORD of hosts; The children of Israel and the children of Judah were oppressed together: and all that took them captives held them fast; they refused to let them go.