The priests who collect tithes are me who die, so Melchizedek is greater than they are because we are told that he lives on. In addition, we might even say that these Levites – the ones who collect the tithe – paid a tithe to Melchizedek when their ancestor Abraham paid a tithe to him. For although Levi wasn’t born yet, the seed from which he came was in Abraham’s body when Melchizedek collected the tithe from him.
So if needthe priesthood of Levi, on which the law is based, could have achieved the perfection God intended, why did God need to establish a different priesthood, with a priest in the order of Melchizedek instead of the order of Levi and Aaron?
And if the priesthood is changed, the law must also be changed to permit it. For the priest we are talking about belongs to a different tribe, whose members have never served as the altare as priests. What I mean is, our Lord came from the tribe of Judah, and Moses never mentioned priests coming from that tribe.
(vv. 11-14, NLT)