If we lend something to other people, when we need the thing back, we will unceasingly ask him to return the thing as soon as possible. If he not yet returns, we will urge and urge until he returns the thing.
If we pray with the persistence like this, we should get whatever we ask. However, we will not pray like this to the Father. This is because we do not lend anything to the Father. And the Father doesn’t owe us anything. Even more, we are the ones who need the help. Besides that, we are not dare to pray like this to the Father. Because, we know that we are sinners. Of course, we should confess our sins. Therefore, if we really have petitions, we need to confess our sins to the Father first, and ask for forgiveness. To ask for forgiveness, we need to forgive others. Then, we can ask from God.
Even more, to avoid the condemnation of our conscience which will affect our faith, we need conversion.