Do you ever find yourself stuck in a prayer loop, asking for the same thing or bringing up the same issue to God over and over again? You wonder if he doesn't get tired of it. I mean, you try not to bore your friends, and your spouse is already fed up with you talking about it (if you were even brave enough to expose your pain/sorrow/disgust/misery). So you tell it to God and find yourself convinced he's pretty sick of it too.
There are two parables in the gospel of Luke that seem to be about praying for the same thing, examples of people importuning God until he finally gives up and just does what they ask.
In the parable of the unexpected guest (Luke 11:5-8), Jesus says imagine you've got guests who have dropped in at an ungodly hour and you need something to feed them, but the convenience store around the corner has closed. So you visit your good friend, knock on the door until he wakes up and hear him grumble from within, "Hey man, everyone's asleep here, go bug someone else." But you keep pounding on the door and make such a racket that he gets up and gives you what you need, not because he's your friend but because you wouldn't give up.
Then there's the story of the judge and the importunate widow (Luke 18:1-8). This judge is no paragon and doesn't really have compassion for anyone who comes to his court. For days he's had to put up with this one lady -- young or old, Jesus doesn't say -- who keeps asking for vindication against her adversary. In an era when widows didn't have Social Security or much in the way of pensions or legal protections, she sounds like a mighty courageous woman. She keeps it up until he finally gives in simply because all that bothering, that badgering, is wearing him out.
You can go down the wrong rabbit hole by thinking of the two parables as descriptors of God: the lazy friend, the unjust judge. Better to see them as models for prayer. Pound on your friend's locked door at midnight; show up at court so often that the clerks know your name. Ask God for what you want as much as it occupies your mind, because it's those nagging, horrible, conflicting, heartbreaking needs that linger in your mind beyond one quick begging session. If you're stuck in a prayer loop, stay in it as long as you need to. God understands. He's even better than that judge or friend.
The danger is for us to think that something like prayer should be unspeakably holy, polite and full of exalted thoughts. Fine, if you like. But it can also be rude, angry and importunate -- take a look at a few psalms. Jesus has a pretty good understanding of human nature. When we're in pain we repeat ourselves.
So why would God let us? Why would he put up with it? Well, the same way that our therapists let us go on and our loved ones hear us out and our journals see the same words come up with too much frequency. We need to blow off steam. Moreover, when we repeat ourselves in a healing context like prayer, we start to see the sense of it. In our petitions to God, we find ourselves becoming braver, stronger, more confident, surer of ourselves, like that courageous widow. The language of prayer, like some exercise of cognitive therapy, is part of the cure. Persistence means everything.
Of course God knows what we need better than we know ourselves and wants us to be the good, decent, steadfast, loving, un-tortured souls we believe we can be. He even lets us tell him, and tell him a lot. He answers us and hears us. "O Lord, hear my prayer," we say like the psalmist and believe it by saying it. Over and over again.