God never opens doors that have been closed.  He opens other doors, but He reminds us that there are doors which we have shut, doors which need never have been shut.

From Luke 19:42:  “[Jesus weeps over Jerusalem] As He came near and saw the city, He wept over it, saying, ‘If you, even you, had only recognized on this day the things that make for peace!  But now they are hidden from your eyes.'”