So we fasted and sought our God for this: and he was entreated of us.
Therefore also now, said the LORD, turn you even to me with all your heart, and with fasting, and with weeping, and with mourning:
So the people of Nineveh believed God, and proclaimed a fast, and put on sackcloth, from the greatest of them even to the least of them.
Sanctify you a fast, call a solemn assembly, gather the elders and all the inhabitants of the land into the house of the LORD your God, and cry to the LORD,
However, this kind goes not out but by prayer and fasting.
2 Chronicles 20:3
And Jehoshaphat feared, and set himself to seek the LORD, and proclaimed a fast throughout all Judah.
And Jesus said to them, Can the children of the bridal chamber mourn, as long as the bridegroom is with them? but the days will come, when the bridegroom shall be taken from them, and then shall they fast.
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 to Jerusalem.
Moreover when you fast, be not, as the hypocrites, of a sad countenance: for they disfigure their faces, that they may appear to men to fast. Truly I say to you, They have their reward. But you, when you fast, anoint your head, and wash your face; That you appear not to men to fast, but to your Father which is in secret: and your Father, which sees in secret, shall reward you openly.