Bypass Apple ID

No you cannot bypass the iOS 7 Activation Lock. It is there to stop pesky thieves steeling and hijacking peoples phones.

You must get in contact with the person you purcahsed the iPhone off and ask them to remove the device from there iCloud account, only then will you be able to activate the phone using your own Apple ID.

If you are unable to get in contact with the person you purchased this iPhone off then you could try giving Apple Technical Support a call and see what they can do, but I doubt they will do anything for secrity purposes.

There is no way to bypass the activation lock, without that information the phone is useless.

This is what Activation lock is in detail

http://support.apple.com/kb/HT5818