We look at opportunities and feel many things. One common reaction is excitement with fear. The joy of feeling something new combined with the fear of the unknown.
To be able to make use of the opportunity we need to overcome the fear and embrace the excitement. One way to do that would be to look at an opportunity not as a single occurrence but a beginning. Kevin Kelly calls it an opportunity cascade. One door will open many doors, which will open many more doors.
As for overcoming the fear, we already know that there is a way.