Isaiah 58:5 “Is this the kind of fast I have chosen, only a day for a man to humble himself? Is it only for bowing one's head like a reed and for lying on sackcloth and ashes? Is that what you call a fast, a day acceptable to the Lord?”
The Lord here questions our approach and attitude in what we call a fast. God tells us that He is not so much looking at our outer actions when we fast, but at what is going on in our hearts. The crucial message that the Lord is teaching us in this passage, is that the Lord will not hear us or respond to our prayers if we fast and pray with a selfish heart. This is so serious that it is important for us to try and understand more about this unacceptable fast:
The Lord has abhorrence for all sin, and particularly towards selfishness. Selfishness epitomises all sin and Billy Graham has said that covetousness or selfishness is the root of all sin. Selfishness is the root of the pride and self-elevation that caused Lucifer/Satan to fall from heaven, and is the same root of the temptation he then brought before Eve and Adam in the garden, which then caused the fall of man. This selfishness is the root of the rebellion that He wants His prophets to shout out so loudly to His people.
If we do a root cause analysis for all the immorality, crime, corruption, violence, wars in this world, and try to find the foundational cause of all these things, we will find that man’s selfishness is behind it all. However I believe that the first fruit or causal effect of our selfishness that God notices on earth is the oppression, hunger, homelessness, nakedness and suffering of the poor. The poor are the greatest casualties of the whole wicked saga.
Selfishness causes the rich to get richer, and the poor to get poorer, and the powerful to get more powerful and lifted up, and the weak, weaker, hungrier and more oppressed. This is the great injustice and oppression that is abhorrent to God, and its root cause is selfishness. Perhaps we can begin to understand why He won’t hear us when we fast and pray with a selfish heart.