A lock is a symbol of some problems, which you fear to face. You should not worry because life without any difficulties is not a life. If you are standing behind a locked door in your dream, it indicates that you will soon have to make a choice. This dream encourages you to follow a more difficult way as it will bring you a bigger reward.
Opening or closing a door in a dream is a recommendation to do the same in real life. You should either be open to new acquaintances or dedicate more time to yourself, respectively.
