Gen 9:23

וַיִּקַּח֩ שֵׁ֨ם וָיֶ֜פֶת אֶת־הַשִּׂמְלָ֗ה וַיָּשִׂ֨ימוּ֙ עַל־שְׁכֶ֣ם שְׁנֵיהֶ֔ם וַיֵּֽלְכוּ֙ אֲחֹ֣רַנִּ֔ית וַיְכַסּ֕וּ אֵ֖ת עֶרְוַ֣ת אֲבִיהֶ֑ם וּפְנֵיהֶם֙ אֲחֹ֣רַנִּ֔ית וְעֶרְוַ֥ת אֲבִיהֶ֖ם לֹ֥א רָאֽוּ׃

Then Shem and Japheth took a garment and placed it across their shoulders, and walking backward, they covered their father’s nakedness. Their faces were turned away so that they did not see their father’s nakedness.