Leviticus 19:6

New American Bible - revised edition

It must be eaten on the day of your sacrifice or on the following day. Whatever is left over until the third day shall be burned in fire.

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You must not keep any of it beyond the morning; whatever is left over in the morning must be burned up.

When you sacrifice your communion sacrifice to the Lord, you shall sacrifice it so that it is acceptable on your behalf.

If any of it is eaten on the third day, it will be a desecrated offering and not be accepted;