Original: According to available documents , the Persian language is '' the only Iranian language '' for which close phylological relationships between all of its three stages are established and so that Old , Middle , and New Persian represent one and the same language of Persian , that is New Persian is a direct descendent of Middle and Old Persian .
Simplified: Persian is a very old language , and linguists have names for three different versions of Persian that were used in three different times . Old Persian was spoken in the first Persian empire , under the Achaemenid kings , including Cyrus and Darius the Great .