Jesus accomplished this by reaching the end-stage, i.e. working through the entire process to reach the final phase of what God had in mind for him. It is referred to as perfection or maturity. It is well-illustrated with the old pirate’s telescope, unfolding (extending out) one stage at a time to function at full-strength (capacity effectiveness). When this happened God announced that Jesus could intercede for us. He is our perfect and mature priest.
Now this is good news. Jesus went through everything he needed to so that he could demonstrate perfectly that he is God’s son.
While he lived on earth, anticipating death, Jesus cried out in pain and wept in sorrow as he offered up priestly prayers to God. Because he honored God, God answered him. Though he was God’s Son, he learned trusting-obedience by what he suffered, just as we do. Then, having arrived at the full stature of his maturity and having been announced by God as high priest in the order of Melchizedek, he became the source of eternal salvation to all who believingly obey him. (Hebrews 5:10 The Message)