http://www.syndie.i2p/manual.html
If --delete is specified, the messages themselves
will be removed from the archive as well as the database decrypt [(--message $msgId|--channel $channelId)] [--passphrase pass] If the message or channel metadata in question was imported into the
database before, but could not be decrypted at the time, you can attempt
to decrypt it again later, using either the provided passphrase or the
currently logged in nym's set of reply and channel read keys. // watch...