When we fast, it is not to get God to change His mind, as you can see in 2 Samuel 12 when King David fasted when his son was sick and died. Fasting is done to bring us closer to God so we can see ourselves and allow us to learn what God wants to do in us so we could become equipped to do service for Him as outlined in Isaiah 58.
In the story of Esther, it wasn't the fast that saved the entire nation of Israel. When she asked everyone to come together and fast, she was given courage to approach the king unsummoned even if it meant her death. She was given wisdom on how to petition the king to save her nation. She was given favor and was allowed to approach the King. The fast even changed the king's heart and he granted Esther's request even before he heard what it was asked
Make sure the when you are fasting, it is for the will of God and not out of religious duty. When you read the account of Jezebel and Ahab, they fasted and killed a man to obtain his land and God punished them.
Isaiah 58 points out that the fast that God calls would: loose the chains of injustice, untie the cords of the yoke, set the oppressed free and break every yoke, change your heart so you can feed the hungry, shelter the homeless, clothe the naked and knit the family together, bring forth healing and God will be your protector. Most importantly as you call on God, He will answer. Wow!! I don't know about you, but sounds like God's fast has more to offer.
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