Since the Priestly literature only allows for descendants of Aaron to be priests (see #152, #153-154, #160-161), while the Deuteronomic corpus identifies the whole tribe of Levi as priests, there are obviously going to be other contradictory commandments between these two sources, which represent competing priestly schools.
For example, Leviticus explicitly has Yahweh command that only Aaron and his sons, that is the descendants of Aaron, can eat the remaining portions of the people’s sin-offerings, elevation-offerings, and grain-offerings. Conversely, Deuteronomy 18 presents Yahweh commanding such portions for the entire Levite tribe.
Again, as discussed in other entries, when we compare the different texts of the Bible, and in this case the commandments of Yahweh, we are able to actually see, and appreciate, that these texts were written to legitimate and authenticate each priestly guild’s positions. So in this case, the Aaronid priest writing the scroll that will later be title Leviticus, uses Yahweh as a mouthpiece to legitimate his own social position and the benefits that come with his position—the priestly portions of the sacrifices.
Likewise, the Levite scribe of Deuteronomy employs the very same literary technique—namely, he has Yahweh legitimate his guild’s positions and ideology. In fact, we can make the generalization that this is on the whole what ancient literature did. And studying the Bible is one of the best examples of this literary technique used throughout the ancient Near East.