Jesus Christ presents the ability to importune as one of the elements of prayer, one of the main conditions of prayer. The prayer of the Syrophenician woman is an example of the matchless power of persistence in prayer . (Matthew 15)
Without persistence, prayers may go unanswered. Importunity is made up of the ability to hold on, to continue, to wait with unrelaxed and unrelaxable grasp, restless desire, and restful patience. Importunate prayer is not an incidental occurrence, but the main thing not a performance, but a passion; not an option, but a necessity.
Prayer in its highest form and its grandest success, assumes the attitude of a wrestler with God. Prayer is the contest, trial, and victory of faith - a victory not secured from an enemy, but from Him who tries our faith that He may enlarge it. He tests our strength to make us stronger. Few things give such quickened and permanent vigor to the soul as a long, exhaustive season of importunate prayer.
There is neither encouragement nor room in the religion of the Scriptures for feeble desires, listless efforts, lazy attitudes. All must be strenuous, urgent, ardent. Inflamed desires and impassioned, unwearied insistence are the things that delight heaven.
God would have His children unalterabley in earnest and persistently bold in their efforts. Heaven is too busy to listen to half-hearted prayers or to respond to hasty, thoughtless calls to God.
Importunity, it may be repeated, is a condition of prayer. We are to press the matter, not with vain repetitions, but with urgent repetitions. We repeat, not to count the times, but to gain the answer to our prayer. We cannot quit praying, because heart and soul are in our prayers. We pray 'with all perseverance' (Eph 6:18); we hang on to our prayers because we live by them. We press our pleas because we must have them or die.
Pray and never faint, is the motto Christ gives us for praying. It is the test of our faith, and the more severe the trial and the longer the waiting, the more glorious the results."
excerpts taken from "E. M. Bounds on Prayer"