St Augustine comments that it is not the length of prayer, but persistence in it that the Lord praises; God knows what we need before we ask for it. The widow, because of her persistence could not be treated with contempt even by an unjust Judge; how much more, therefore, will the only Just Judge heed our petitions?
Origen reminds us that God is with those who pray, and appeal with those who make appeals to Him; but He does not pray with those who do not pray, neither can Christ be our advocate if we do not appeal to Him and the Father.
St Cyril of Alexandria says that the parable assures us that God will bend his ear to those who pray to him with earnestness and constancy; but we cannot expect the same if we are negligent or careless in our prayer. If the constant petitions of the widow conquered even the unjust judge, then He who loves mercy and hates iniquity will not turn from us – if we turn to Him; but will we; do we?
St Ephrem the Syrian tells us the the iniquity of the judge consisted in his acting contrary to the justice of God, and he was wicked in so far as he rebelled against God and followed the devices and desires of his own heart; are we better than this man? Prayer was, however, more persistent than iniquity and evil, and triumphed over them; so too can it be with us if we have faith and persist in prayer and in Godly ways. We can prevail on on the Grace and Justice of God.
St Augustine cautions us against the facile view that the unjust judge is meant to be an allegory of God. He provides an example of and unjust man who despite his wickedness cannot disregard those who bother him continuously. If even the unjust do as much, how much more does Our Heavenly Father do for those who will turn to the one who is Just and Good?
St Cyril reminds us that the people of this world sell the word of righteousness and make many abandon sound faith. They involve them in the invention of devilish error. This is why Jesus asks if the Son of Man will find any faith when He comes again. He foretells that the love of many will grow cold. In the end times some will depart from a correct and blameless faith, following after seducing spirits and listening to the fales words of those who have a seared conscience (1 Tim 4:1-2). We, by contrast, must come near to God as faithful servants, begging Him that their wickedness and attempts against His glory might be in vain.