וְהַנּוֹתָ֖ר מִבְּשַׂ֣ר הַזָּ֑בַח בַּיּוֹם֙ הַשְּׁלִישִׁ֔י בָּאֵ֖שׁ יִשָּׂרֵֽף׃
But that which remaineth of the flesh of the sacrifice on the third day shall be burnt with fire.
Read kabbalistic (mystical) interpretation of Leviticus 7:17: and classical mystical sources.