One time in our lifetime we've heard a knock at door posts and were expected to respond to them. It is not expected for anyone to ignore a knock since we hardly know the 'door knockers' or even the reason for the knock.
For the case at hand, you know the person knocking. You've heard from at least one of his spokesperson either on one to one, through an ad. or may be you being part of the audience.

For how long will you close this door? Open up and experience the best moment in your life. Open up to God's wonderful experience and you'll never regret.