וַיֵּ֣דַע אוֹנָ֔ן כִּ֛י לֹּ֥א ל֖וֹ יִהְיֶ֣ה הַזָּ֑רַע וְהָיָ֞ה אִם־בָּ֨א אֶל־אֵ֤שֶׁת אָחִיו֙ וְשִׁחֵ֣ת אַ֔רְצָה לְבִלְתִּ֥י נְתָן־זֶ֖רַע לְאָחִֽיו׃
俄南知道這後裔不歸他自己，所以每當他與他哥哥的妻子同房的時候，就洩在地上，免得給他哥哥留下後裔。
Targum Jonathan
And Onan knew that they would not call the children after his name, and it was, when he entered to the wife of his brother, that he corrupted his work upon the earth, that he might not raise up children to his brother's name.