You can submit your application with all of the required supporting documents and your passport. If you require your passport back in advance of the decision on the application, you should submit a complete copy of your passport (every page) which will enable us to make a provisional decision on your application. Once you have returned to Germany you can re-submit your passport to us for the visa to be affixed in the event that your application is successful.
Please include a note to the Visa team explaining why you need your passport back.
However, you are responsible for ensuring that you re-submit your passport.