4th Sunday of Advent
This Sunday, the second reading will be from Hebrews 10:5-10. I’d suggest reading verses 1-18, for a more full context, as well as the other readings.
One who was familiar with the sacrifices of the Old Testament would know that one day each year, the high priest would enter the Holy of Holies to make sacrifices for the sins of the people - would know that he first made a sacrifice for his own sins before he was worthy to offer sacrifices for the whole people. This is exactly the intended audience, and the writer to the Hebrews lays out the ways in which Jesus was the fulfillment of the Old Testament law. Jesus says in Matthew 5:17 that he came not to abolish the the law, but to fulfill it.

