it is because a definite faith is lacking to appropriate the spiritual blessings we desire that so many prayers appear to be fruitless. for such an act of faith not everyone is ready. in many cases, there is not a spiritual capacity to accept the blessing; it is where there is no true conviction of the sin of disobedience and consequently no true sorrow for it. often there is not a strong longing or purpose to obey God completely in everything. in others, there is no deep interest in the message of scripture: that God wants to perfect us to do his will, by His working in us that which is pleasing in His sight.
in such cases the christian is content to remain a babe. he wants only the milk of consolation. he is not mature enough to bear the strong meat of which Jesus ate: doing the will of His Father.
[a life of obedience, andrew murray, 1982]