There are two passages in the Torah which detail the laws of a korban chatas (sin offering), one in Parshas Vayikra and the other in Parshas Tzav. These two passages are very close to each other; why did the Torah discuss it twice, and in two different places?
The same is true regarding the Asham (guilt-offering) and Shalmei Nedava (involuntary peace-offerings), that those sacrifices are discussed in both Parshas Vayikra and Tzav, albiet in slightly different ways. Why?
(I'm not asking about what halachos are learned out from this repetition or from the second paragraph, but why the Torah needed two paragraphs a few chapters away from each other to teach us these laws)