Why is Christ considered our altar and sacrifice?

In the sermon, it's explained that Christ is not only our sacrifice but also serves as the altar on which He offered Himself. This unique role is pivotal in understanding the nature of Christian worship. Unlike Old Testament sacrifices that were merely symbols pointing to greater realities, Christ's sacrifice is the reality that these shadows foreshadowed. His death outside the camp signifies the taking upon Himself of our sins, which were offensive to God. Thus, believers approach God through Christ, who is the living altar, enabling us to offer spiritual sacrifices such as praise and thanksgiving rather than animal offerings.