5.In what way does the writer of Hebrews show that Christ and His salvation

By the fact that Christ was made a priest after the order of Melchizedek, and Melchizedek is greater than Abraham. Therefore if Melchizedek is greater than Abraham, and Abraham was the ancestor of Levi, who was the ancestor of Aaron, then Christ and His salvation are greater than Aaron and the Levitical priesthood.

Levi, still in the body of Abraham, paid tithes to Melchizedek when Abraham paid tithes. Since Aaron, the High Priest, descended from Levi, then Aaron also paid tithes to Melchizedek, in a manner of speaking.

We understand, therefore, that the Levitical priesthood was imperfect. If it had been perfect, there would have no need to install a priest from another order—a superior order—the order of Melchizedek.