וַיִּקַּ֤ח מֹשֶׁה֙ אֶת־הֶ֣חָזֶ֔ה וַיְנִיפֵ֥הוּ תְנוּפָ֖ה לִפְנֵ֣י יְהוָ֑ה מֵאֵ֣יל הַמִּלֻּאִ֗ים לְמֹשֶׁ֤ה הָיָה֙ לְמָנָ֔ה כַּאֲשֶׁ֛ר צִוָּ֥ה יְהוָ֖ה אֶת־מֹשֶֽׁה׃
And Moses took the breast, and waved it for a wave-offering before the LORD; it was Moses’portion of the ram of consecration; as the LORD commanded Moses.
Read kabbalistic (mystical) interpretation of Leviticus 8:29: and classical mystical sources.