This parable Jesus tells is interesting.
It's very different that Luke begins the parable by summarizing the point of the parable. I don't feel like that happens in the Bible, the stories seem to be meant to stand alone...they are a little up to interpretation...they are meant to be explained by the Holy Spirit. But in this story Luke says "Then Jesus told his disciples a parable to show them that they should always pray and not give up."
And it makes sense that he explains the point of the parable because I think this parable in particular could EASILY get confused.
A widow keeps and keeps coming to a terrible leader who doesn't care about God or people. She keeps begging him everyday for her rights and finally he gives in because he's annoyed. Basically that's the premise.
It could be very easy to get confused...is God saying He's a terrible leader? Is God saying we could annoy Him to the point He gives in?
No. We know who God is. He is loving, patient, and compassionate.
He says "Will not God bring about justice for His chosen ones, who cry out to Him day and night? Will He keep putting them off?" No, He will not. God listens, God cares. Even if we don't see much happening, we should keep praying and believing that God is right there listening and He does not make us wait any longer than we need to.
It reminds we of Matthew 7:9-11
"Which of you, if your son asks for bread, will give him a stone? Or if he asks for a fish, will give him a snake? If you, then, though you are evil, know how to give good gifts to your children, how much more will your Father in heaven give good gifts to those who ask him!"
Pray, pray, pray. Because with God nothing is impossible! And because He knows what we need, He knows what is best for us and He does not withhold from us, not forever.