Daniel 1:21 Kabbalah

וַֽיְהִי֙ דָּֽנִיֵּ֔אל עַד־שְׁנַ֥ת אַחַ֖ת לְכ֥וֹרֶשׁ הַמֶּֽלֶךְ׃ (פ)

And Daniel continued even unto the first year of king Cyrus.

Read kabbalistic (mystical) interpretation of Daniel 1:21: and classical mystical sources.