וַיִּקְרָ֣א מֹשֶׁ֗ה אֶל־בְּצַלְאֵ֘ל וְאֶל־אָֽהֳלִיאָב֒ וְאֶל֙ כָּל־אִ֣ישׁ חֲכַם־לֵ֔ב אֲשֶׁ֨ר נָתַ֧ן יְהוָ֛ה חָכְמָ֖ה בְּלִבּ֑וֹ כֹּ֚ל אֲשֶׁ֣ר נְשָׂא֣וֹ לִבּ֔וֹ לְקָרְבָ֥ה אֶל־הַמְּלָאכָ֖ה לַעֲשֹׂ֥ת אֹתָֽהּ׃
E Moshe chamou a Betzalel e a Oholiav e a todo homem hábil de coração, ao qual o Senhor deu sabedoria em seu coração, todo aquele cujo coração o moveu a se aproximar do trabalho para fazê-lo.
Mishneh Torah, Sanctification of the New Month
And due to the length of the years and the multitude of experiments and research, the ways of this calculation became known to some sages. Moreover we have traditions and proofs from the Sages about their main principles written in books that are not known to all. And because of all these things, it is fitting in my eyes to explain the ways of this calculation – in order that it be prepared for the one whose heart fills him to approach this discipline to do it.