Always pray and never give up.

Prayer is not a transaction. Prayer is not something we give God in exchange for services. Prayer is relationship. Persistent prayer is not about wearing God down. It is about remaining close to the One who loves us. When the result of our prayer is not what we think, rather than giving up or resorting to manipulation we keep the conversation with God going. Persistent prayer forms Kingdom faithfulness within us. Prayer is a two way street, God does not mind us repeating ourselves. We do however need to be careful that we are listening to Him.

It is easy to think of prayer as only asking for things from God. That is part of what this parable is about but not all. In v7 we have this “So don’t you think God will surely give justice to his chosen people who cry out to him day and night?”  Cry is a wordless call.

Prayer includes something we often forget today: Lament. The Bible is full of lament. Nearly one third of the Psalms express it. Lament is looking at our situation, especially when our situation is giving us pain and problems, trials and tribulations and crying out. 

Lament is different from whining or being downhearted or having a pity party. Lamenting is taking the situation to God rather than letting your head drop and acting as if you are trapped in an unfeeling, blind universe. Lament is being honest with God and honest about our pain. Lamenting is not a lack of faith. It takes a lot of trust and loyalty to look to God in our pain and problems.
This parable is telling us we aren’t forced to pretend everything is all fine. Express your complaints to God and cry out to him to do something about the situation. Your emotions will never be too strong for God. If your pain persists? Keep on crying out to God.

Lament is not weak faith. It is faith refusing to let go of God in pain.

https://undeceptions.com/podcast/god-laments/ 

The end of v8 is a sober warning. But when the Son of Man  returns, how many will he find on the earth who have faith? Jesus wonders if he will find followers loyal to him when he returns. And so he urges us to always pray.