God cannot hear the prayers on our lips often because the desires of our heart after the world cry out to Him much more strongly and loudly than the our desires for Him.
Andrew MurrayThe only humility that is really ours is not that which we try to show before God in prayer, but that which we carry with us, and carry out, in our ordinary conduct; the insignficances of daily life are the importances and the tests of eternity, because they prove what really is the spirit that possesses us.
Andrew Murray