'Fast' in the Bible

The Lord said to Satan, “Have you considered and reflected on My servant Job? For there is none like him on the earth, a blameless and upright man, one who fears God [with reverence] and abstains from and turns away from evil [because he honors God]. And still he maintains and holds tightly to his integrity, although you incited Me against him to destroy him without cause.”

Then his wife said to him, “Do you still cling to your integrity [and your faith and trust in God, without blaming Him]? Curse God and die!”

“He trusts in his house, but it does not stand;He holds tightly to it, but it does not endure.

“My feet have carefully followed His steps;I have kept His ways and not turned aside.

“I hold fast my uprightness and my right standing with God and I will not let them go;My heart does not reproach me for any of my days.

When the dust hardens into a massAnd the clods stick together [because of the heat]?