In Luke 18 Jesus tells two stories which tell us something about how to pray. How we need to confidently keep on praying and not give up because God IS good; and we need to come to God humbly being honest about our need of him. A sense of injustice and a sense of unworthiness can be two things that drive us away from God. Jesus says let those things drive you TO God and know he is there and will hear.

Yes the temptation to give up is real, but that's where faith in who God is, kicks in. 

Jesus tells parables about three lost things... and how this shows the significance of a change of mind to respond to God.

Jesus speaks about possessions, worry, and how this relates to the kingdom and being ready for God.

In this passage we see Jesus in some real conflict! Speaking strongly against the religious leaders and challenging hypocrisy.