Malachi 3 : 1-4
Now I am sending My messenger ahead of Me to clear the way; then suddenly the Lord for whom you long will enter the sanctuary. The envoy of the covenant which you so greatly desire already comes, says YHVH of hosts. Who can bear the day of His coming and remain standing when He appears? For He will be like fire in the foundry and like the lye used for bleaching.
He will be as a refiner or a fuller. He will purify the sons of Levi and refine them like gold and silver. So YHVH will have priests who will present the offering as it should be. Then YHVH will accept with pleasure the offering of Judah and Jerusalem, as in former days.
(Alternative reading : Hebrews 2 : 14-18)
And because all those children share one same nature of flesh and blood, Jesus likewise had to share this nature. This is why His death destroyed the one holding the power of death, that is the devil, and freed those who remained in bondage all their lifetime because of the fear of death.
Jesus came to take by the hand not the angels but the human race. So He had to be like His brothers and sisters in every respect, in order to be the High Priest faithful to God and merciful to them, a priest able to ask pardon and atone for their sins. Having been tested through suffering, He is able to help those who are tested.