במדבר, פרק י״ח, פסוק כ״ה

God initiates a set of instructions directing the Levites to set aside a specific offering from the tithes they collect. This communication is directed exclusively to Moses, intentionally leaving Aaron out of the conversation. The reason for this exclusion is a matter of propriety. The upcoming instructions require the Levites to give a tithe from their own tithes directly to Aaron the Priest. It would be inappropriate for Aaron to be the one commanding the Levites to hand over gifts intended for his own benefit [אבן עזרא].

The instructions given to Moses detail the precise method for setting aside this offering, establishing strict boundaries based on the status of the produce. A fundamental rule is that produce grown within the Land of Israel cannot be separated to exempt produce grown outside of it. This mirrors the restriction against using a newly harvested crop to exempt an older crop. The guiding principle behind these rules is that an offering cannot be taken from one batch to cover another if the two do not share the exact same status. This concept is not unique to this particular offering; it closely parallels the regulations governing the separation of dough and the tithing of animals.

Expanding on the nature of these obligations, another perspective links the core essence of this command to the specific laws that characterize the Second Tithe [צפנת פענח].