A key part of prayer is persistence. Often, it's not enough simply to ask. God wants us to not be afraid to be persistent. How do we know that? Jesus told a story about a widow who'd been in a dispute with an enemy. She approached a judge and decided she wasn't going to give up pleading with him. Finally he gave in and said 'I'm going to see that she gets justice, because she is wearing me out with her constant requests' (Luke 18:5)! Wow, what a great attitude to have in prayer, right? Never giving up.
But wait...what about that judge? He sounds a little off. Does this story mean that God is indifferent to our needs? Does He really care about our prayers, or does He only give in to us because we've nagged Him enough? Not at all. The judge in this story is unjust; Jesus made his story's judge a bit of a grumpy old man to make His point: if this tired, grumpy old man gives in, 'don't you think God will surely give justice to His chosen people who cry out to Him day and night? Will He keep putting them off' (Luke 18:7)? Remember that this is God in Heaven, who loves to see you blessed.
If you don't see an answer to that prayer, keep asking Him. He's not reluctant to answer you, but He's working things to give you the very best, and wants you to get even closer to Him in the meantime.
So what now? Pray and pray again for something you've given up praying for. God is willing and is waiting.
Soulfood : Is 8-11, Jn 6:1-24, Ps 126, Prov 27:17-19