I have 2 files :-
1) f1.txt and f2.txt.Both contain some text as -

2)Now I did :
output: I got them to be equal.
3) I encrypted them using gpg and with the SAME paraphrase :-
4)Now I did :
[...]#cmp f1.txt.gpg f2.txt.gpg
(OR)
[...]#diff f1.txt.gpg f2.txt.gpg
[/QUOTE]
output: I got them to be NOT equal.

Can you please tell me why?
My actual intension is to know how to compare any 2 encrypted files to know whether they contain the same text or not without DECRYPTING them!!!!

That is a feature, not a bug. With many algorithms the data is encrypted block by block. And the previous encrypted data block is combined with the current plaintext data block as part of the encryption. To get the ball rolling, the algorithm generates a block a random data to combine with the first plain text data block. During decryption, this initial block of make believe encrypted data is discarded.

Now if the same data is encrypted with the same pass phrase, you can't tell by looking at the data. This is a good thing.

The only way to compare two encrypted data files is to decrypt them. If you don't know both passphrases, the contents of the files are none of your business.