Have you ever gone to a parent to ask for something and they said no? Have you ever made a request of your boss and had that request rejected? What did you do? Did you give up and walk away, or did you keep asking? Chances are, if it was important, if it meant a lot to you, you kept asking. You didn't give up. You persisted until you got them to listen to you and the reasons for your request.
This is what the persistent widow did in the gospels (Luke 18:1-8). Here we have this old widow who needs some justice, so she goes to the judge. He rejects her request for justice. But her request is really important, so she keeps asking. She doesn't give up.
I know when I was a child, whenever my parents rejected a request of mine, I thought they were being unjust. I thought it was unfair that they did not give me what I wanted....that they wouldn't even listen to my argument about why I needed what I was asking for. I, unfortunately, was not a very persistent child, so I normally just dropped the request after my first attempt. Had I persisted, my parents may have at least listened to my argument, and they may have even granted my request.
We all make requests of God in our prayer. It is often my experience that God does not grant my prayer requests...at least not initially. I have, from time to time, seen God as being unjust for not granting my request, for not listening to my arguments. But I continue to be persistent in the hopes that God will eventually listen to and answer my prayers, because I know that God is a just judge.Think about it, if an unjust judge, like in the parable of the persistent widow, will eventually hear and respond to the pleas, helpless widow, how much more will God, who is just, respond to our pleas.
However, take note! The bible passage never indicates that the judge gave the decision that the widow was looking for. All he agrees to do is to "deliver a just decision for her." The widow does not necessarily receive what she wants, but she does receive justice.
Likewise, through persistent prayer, God will eventually hear our pleas, our cries for help. And, like the judge, he won't necessarily give us what we want. But he will give us what we need, what is best for us. God will deliver justice.