Fwd: is there any remote possibility to recover passphrase?

[me at greenest.org]

Hi all and thank you for GnuPG!

I was wondering whether one attacker who'd be in possess of my private and 
public keys, my entire archive of encrypted data, and a common file which for 
sure is just plain the same as an encrypted one of my backup, could in some 
way and time recover my passphrase.

Let's suppose I am a developer which shares some pieces of a project and 
doesn't some others, as such some of the files are plainly available to the 
attacker, and even if I crypt all the files at once with a strong algo and 
gpg, but let my keys available to the attacker, would he theorically be able 
to crack my passphrase and recover all of my archive?

Regards,
greenest