וְיִֽשְׁמַֽעְיָ֧ה הַגִּבְעוֹנִ֛י גִּבּ֥וֹר בַּשְּׁלֹשִׁ֖ים וְעַל־הַשְּׁלֹשִֽׁים׃
and Ishmaiah the Gibeonite, a mighty man among the thirty, and over the thirty;
Read kabbalistic (mystical) interpretation of I Chronicles 12:4: and classical mystical sources.