I posted this as a reply on another thread but then realized it would be a great topic to form a new thread.
Fasting is a very powerful discipline in the life of a believer. I don't know how many fast on any kind of a regular basis and what kind of benefit you see from that fasting. Fasting should be a discipline of a believer just as prayer, time in the word, giving, etc.
But many are a bit confused about why we fast. They see it as a way to convince God we are serious about our prayers. They see it as a way to get prayer answered. Some even see it as some sort of penance.
God spoke through Isaiah that the fast that God had chosen was not one in which we afflict our soul and spread sackcloth and ashes under us as though our fasting somehow causes God to see our affliction and take us seriously because of it where He would no have been predisposed to take us seriously before. (Recall the instruction of Jesus in Matt. 6 about washing your face and being joyful even in your fast because the fast is unto God, not for others to see.) So often we pray and if we don't see any answer we take it up a notch, afflict ourselves, and fast and pray as though that will somehow twist God's arm or change His mind. This is not the fast God has chosen. Obviously it is not a fast for strife, debate, or out of legalism that God has ordained.
But the fast He ordained is this.
Isa 58:6-10
(6) 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?
(7) Is it not to deal thy bread to the hungry, and that thou bring the poor that are cast out to thy house? when thou seest the naked, that thou cover him; and that thou hide not thyself from thine own flesh?
(8) Then shall thy light break forth as the morning, and thine health shall spring forth speedily: and thy righteousness shall go before thee; the glory of the LORD shall be thy rereward.
(9) Then shalt thou call, and the LORD shall answer; thou shalt cry, and he shall say, Here I am. If thou take away from the midst of thee the yoke, the putting forth of the finger, and speaking vanity;
(10) And if thou draw out thy soul to the hungry, and satisfy the afflicted soul; then shall thy light rise in obscurity, and thy darkness be as the noonday:
It is the breaking of bondage in our own lives. We are spirit, soul, and body and only one third of us is born again. We still struggle with the flesh. Fasting breaks the power of the flesh in our lives and causes us to be more sensitive to the Holy Spirit. If we have trouble hearing God's voice, it is probably because we are walking too much in the flesh and not in the spirit. We break these yokes by fasting. Our flesh rises up and says, "I am hungry, feed me." We must rely on the Holy Spirit and say, "No, we will not live by bread alone, but by every word that proceeds from the mouth of God." I have gone without food for 24 hours and it did not phase me. I have decided to fast for 24 hours and within one hour I thought I was going to starve. Fasting food is definitely spiritual, believe me. To maintain a fast takes prayer and reliance on the Holy Spirit.
You can fast things other than food, and it is effective. Some need to fast their smart phones, some the internet, some need to fast Coca-Cola (that has been me from time to time.) Anything that has a hold on our flesh needs to be fasted so that the bondage is broken.
