How do we know Christ alone is the only mediator?

The New Testament emphasizes that Christ is the only mediator (1 Timothy 2:5), which means that he alone intercedes for us before God. His role as our high priest is critical, as demonstrated in the Old Testament with Aaron, who entered the Holy of Holies to offer sacrifices on behalf of the people. The atonement made by Christ surpasses all Old Testament sacrifices as it provides a complete and perfect reconciliation between sinners and a holy God, making him the sole path to salvation and acceptance.