Priestly Handling of the Purification Offering
Leviticus gives the rule, and Hebrews later points back to it when explaining Jesus’ suffering outside the gate. This is a strong “Old hidden / New revealed” connection because the later inspired writer makes the comparison explicit.
Where this fits in the story: Explicitly completes Leviticus 4's purification-offering procedures.
Where Scripture takes it next: Hebrews 13:11–13 — certain/explicit. Hebrews describes bodies of sin sacrifices whose blood is brought into the sanctuary being burned outside the camp, then compares Jesus suffering outside the gate.