Kehillah in Corinth I 9:25-27

Orthodox Jewish Bible

²⁵ And everyone competing in the [Olympic] games in all things exercises shlitah atzmi: those ones, therefore, that they may obtain a perishable wreath; but we, an imperishable.

²⁶ Therefore, I run not as one without a goal that is kovua (fixed, set). I box as not beating the air.

²⁷ But I do more than merely spar with my basar; I pommel it and keep it under strict subjection, so that after I am the maggid to others, I myself will not become declared ineligible.