וַיְדַבֵּ֣ר אִתָּם֮ הַמֶּלֶךְ֒ וְלֹ֤א נִמְצָא֙ מִכֻּלָּ֔ם כְּדָנִיֵּ֣אל חֲנַנְיָ֔ה מִֽישָׁאֵ֖ל וַעֲזַרְיָ֑ה וַיַּֽעַמְד֖וּ לִפְנֵ֥י הַמֶּֽלֶךְ׃
And the king spoke with them; and among them all was found none like Daniel, Hananiah, Mishael, and Azariah; therefore stood they before the king.
Read kabbalistic (mystical) interpretation of Daniel 1:19: and classical mystical sources.