Jesus kind of made a big deal of being persistent when talking with God.
There's the story he told about a woman who got a judge to listen to her case because she just wouldn't take "go away and leave me alone" for an answer.
And have you heard the one where the guy wakes up his neighbor to ask for some bread because he had some unexpected visitors from out of town? He had to keep pounding on the door to get his neighbor to help him out.
All this encouragement to keep at it, and yet the following quote from E. M. Bounds still rings so very true.
I think Christians fail so often to get answers to their prayers because they do not wait long enough on God. They just drop down and say a few words, and then jump up and forget it and expect God to answer them. Such praying always reminds me of the small boy ringing his neighbor's doorbell, and then running away as far as he can go.
Truth is...I don't know if it's a wait-for-God's-perfect-timing thing or a test that helps us find out just how much we really want or need what we're asking for. Or maybe it's so we more fully recognize that every good and perfect gift comes from above (James 1:17). Whatever it is, it seems to be God's standard operating procedure, and I need to be encouraged to keep in step with him.