This is worth some thought. Persistance is something I admire and it’s interesting I came across it this afternoon after reading this on Hannah. Yes there are times when the answer simply is no. It’s a good thing to still have hope, God’s plan is for good and not harm.

Interestingly, though Christians today speak of doors that are closed, Scripture does not. The need for open doors certainly implies the existence of some that are closed. But that doesn’t seem to be the mentality of Paul. If he were sovereignly prevented from pursuing a plan, and yet the plan itself was sound, he simply waited and tried again later. He did not view a blocked endeavor as a closed door sign from God that his plan was faulty.” – Friesen (Decision Making and the Will of God)