In Matthew 18:19-20 tells us :"Again, I tell you that if two of you on earth agree about anything you ask for, it will be done for you by my Father in heaven. For where two or three come together in my name, there am I with them.".  Matthew 6:9-13 tells us how to pray.  Yet, even if we pray exactly as Matthew 6:9-13, some Christians are still in hunger (they still strugule with their daily bread, still face their debt on their credit card....).

How to explain?