וַיִּרְכְּס֣וּ אֶת־הַחֹ֡שֶׁן מִטַּבְּעֹתָיו֩ אֶל־טַבְּעֹ֨ת הָאֵפֹ֜ד בִּפְתִ֣יל תְּכֵ֗לֶת לִֽהְיֹת֙ עַל־חֵ֣שֶׁב הָאֵפֹ֔ד וְלֹֽא־יִזַּ֣ח הַחֹ֔שֶׁן מֵעַ֖ל הָאֵפֹ֑ד כַּאֲשֶׁ֛ר צִוָּ֥ה יְהוָ֖ה אֶת־מֹשֶֽׁה׃
Uniram o choshen com suas argolas às argolas do efod com um cordão de azul, para que ficasse sobre o cinto do efod, e o choshen não se deslocasse do efod, conforme o Senhor ordenou a Moshe. {פ}
Mishneh Torah, Negative Mitzvot
Not to compound aught after the formula of the incense, as it is said, “…. ye shall not make unto yourselves according to the composition thereof” (Ex. 30:37).
Mishneh Torah, Negative Mitzvot
That the breastplate shall not be loosened from the ephod, as it is said, “That the breastplate be not loosed from the ephod” (Ex. 28:28).