וְעָשִׂ֜יתָ לְאַהֲרֹ֤ן וּלְבָנָיו֙ כָּ֔כָה כְּכֹ֥ל אֲשֶׁר־צִוִּ֖יתִי אֹתָ֑כָה שִׁבְעַ֥ת יָמִ֖ים תְּמַלֵּ֥א יָדָֽם׃
And thus shalt thou do unto Aaron, and to his sons, according to all that I have commanded thee; seven days shalt thou consecrate them.
Read kabbalistic (mystical) interpretation of Exodus 29:35: and classical mystical sources.