2 Samuel 12:21
Then said his servants unto him, What thing [is] this that thou hast done? thou didst fast and weep for the child, [while it was] alive; but when the child was dead, thou didst rise and eat bread.
Go, gather together all the Jews that are present in Shushan, and fast ye for me, and neither eat nor drink three days, night or day: I also and my maidens will fast likewise; and so will I go in unto the king, which [is] not according to the law: and if I perish, I perish.
[Is] not this the fast that I have chosen? to loose the bands of wickedness, to undo the heavy burdens, and to let the oppressed go free, and that ye break every yoke?
Then the king went to his palace, and passed the night fasting: neither were instruments of musick brought before him: and his sleep went from him.
And I set my face unto the Lord God, to seek by prayer and supplications, with fasting, and sackcloth, and ashes:
Sanctify ye 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 unto the LORD,
And when he had fasted forty days and forty nights, he was afterward an hungred.
But the days will come, when the bridegroom shall be taken away from them, and then shall they fast in those days.
As they ministered to the Lord, and fasted, the Holy Ghost said, Separate me Barnabas and Saul for the work whereunto I have called them.
1 Corinthians 7:5
Defraud ye not one the other, except [it be] with consent for a time, that ye may give yourselves to fasting and prayer; and come together again, that Satan tempt you not for your incontinency.
2 Corinthians 6:5