How do we know Jesus fulfills the role of a high priest?

Jesus Christ is uniquely qualified to be our high priest because He is both fully God and fully man. He offered Himself as the ultimate sacrifice for sin, unlike the Levitical priests who had to make regular sacrifices for their own sins. Scripture emphasizes that He 'offered up Himself' once for all (Hebrews 7:27), and now He 'ever liveth to make intercession' for us (Hebrews 7:25). This means that He continuously appeals to the Father on our behalf, ensuring that we are covered by His righteousness, thus making our relationship with God secure and intimate.