Joel 1:14
Consecrate a fast; proclaim a solemn assembly! Gather the elders and all the residents of the land to the house of the LORD your God, and cry out to the LORD.

Joel 2:15-17
Blow the ram’s horn in Zion, consecrate a fast, proclaim a sacred assembly. / Gather the people, sanctify the congregation, assemble the aged, gather the children, even those nursing at the breast. Let the bridegroom leave his room, and the bride her chamber. / Let the priests who minister before the LORD weep between the portico and the altar, saying, “Spare Your people, O LORD, and do not make Your heritage a reproach, an object of scorn among the nations. Why should they say among the peoples, ‘Where is their God?’”

Acts 12:5
So Peter was kept in prison, but the church was fervently praying to God for him.

Esther 4:16
“Go and assemble all the Jews who can be found in Susa, and fast for me. Do not eat or drink for three days, night or day, and I and my maidens will fast as you do. After that, I will go to the king, even though it is against the law. And if I perish, I perish!”

Nehemiah 9:1-3
On the twenty-fourth day of the same month, the Israelites gathered together, fasting and wearing sackcloth, with dust on their heads. / Those of Israelite descent separated themselves from all the foreigners, and they stood and confessed their sins and the iniquities of their fathers. / While they stood in their places, they read from the Book of the Law of the LORD their God for a quarter of the day, and they spent another quarter of the day in confession and worship of the LORD their God.

Jonah 3:5-9
And the Ninevites believed God. They proclaimed a fast and dressed in sackcloth, from the greatest of them to the least. / When word reached the king of Nineveh, he got up from his throne, took off his royal robe, covered himself with sackcloth, and sat in ashes. / Then he issued a proclamation in Nineveh: “By the decree of the king and his nobles: Let no man or beast, herd or flock, taste anything at all. They must not eat or drink. ...

Matthew 18:19-20
Again, I tell you truly that if two of you on the earth agree about anything you ask for, it will be done for you by My Father in heaven. / For where two or three gather together in My name, there am I with them.”

Acts 1:14
With one accord they all continued in prayer, along with the women and Mary the mother of Jesus, and with His brothers.

Acts 4:24-31
When the believers heard this, they lifted up their voices to God with one accord. “Sovereign Lord,” they said, “You made the heaven and the earth and the sea and everything in them. / You spoke by the Holy Spirit through the mouth of Your servant, our father David: ‘Why do the nations rage and the peoples plot in vain? / The kings of the earth take their stand and the rulers gather together against the Lord and against His Anointed One.’ ...

Ezra 8:21-23
And there by the Ahava Canal I proclaimed a fast, so that we might humble ourselves before our God and ask Him for a safe journey for us and our children, with all our possessions. / For I was ashamed to ask the king for an escort of soldiers and horsemen to protect us from our enemies on the road, since we had told him, “The hand of our God is gracious to all who seek Him, but His great anger is against all who forsake Him.” / So we fasted and petitioned our God about this, and He granted our request.

1 Samuel 7:5-6
Then Samuel said, “Gather all Israel to Mizpah, and I will pray to the LORD on your behalf.” / When they had gathered at Mizpah, they drew water and poured it out before the LORD. On that day they fasted, and there they confessed, “We have sinned against the LORD.” And Samuel judged the Israelites at Mizpah.

Jeremiah 36:9
Now in the ninth month of the fifth year of Jehoiakim son of Josiah king of Judah, a fast before the LORD was proclaimed to all the people of Jerusalem and all who had come there from the cities of Judah.

Daniel 9:3
So I turned my attention to the Lord God to seek Him by prayer and petition, with fasting, sackcloth, and ashes.

Acts 13:2-3
While they were worshiping the Lord and fasting, the Holy Spirit said, “Set apart for Me Barnabas and Saul for the work to which I have called them.” / And after they had fasted and prayed, they laid their hands on them and sent them off.

2 Kings 19:14-19
So Hezekiah received the letter from the messengers, read it, and went up to the house of the LORD and spread it out before the LORD. / And Hezekiah prayed before the LORD: “O LORD, God of Israel, enthroned between the cherubim, You alone are God over all the kingdoms of the earth. You made the heavens and the earth. / Incline Your ear, O LORD, and hear; open Your eyes, O LORD, and see. Listen to the words that Sennacherib has sent to defy the living God. ...