When we fast, God rewards us openly In answer to our prayers!

Luke 4:1-4
And Jesus, full of the Holy Spirit, returned from the Jordan and was led by the Spirit in the wilderness for forty days, being tempted by the devil. And he ate nothing during those days. And when they were ended, he was hungry. The devil said to him, “If you are the Son of God, command this stone to become bread.” And Jesus answered him, “It is written, ‘Man shall not live by bread alone.’”

(Matthew 6:18) That thou appear not unto men to fast, but unto thy Father which is in secret: and thy Father, which seeth in secret, shall reward thee openly.
Be reminded that God rewards sacrifice and rewards when you fast and pray (Esther 5:2) And it was so, when the king saw Esther the queen standing in the court, that she obtained favour in his sight: and the king held out to Esther the golden sceptre that was in his hand. So Esther drew near, and touched the top of the sceptre.

(Jonah 3:5) 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.