To find healing from their sick condition, Jesus instructs them to buy from Him gold having been refined in the fire. If we are willing, the Father will use the fire of sufferings to teach us obedience and to perfect us in Him, just as He did with Jesus.
God’s goal is to have His nature fill and inhabit our bodies, hence, He has to remove all that is in the way of His occupancy. There is all necessary to learn why we should put off the old nature and how to put on the new nature. And Yahweh is not targeting our sinful behavior, as that is just a fruit of what we believe and what we feel and think. He is targeting the sin of wrong belief and the unbelief which is buried down in the deep recesses our soul, as these “enemies” keep us from betting our lives on Yahweh.
He wants us to buy from Him white garments and be covered only with His righteousness, discarding the self-sufficiency of our flesh. All our own coverings are woefully insufficient, nothing but filthy rags. And He wants us to buy from Him eye salve, so we can see the truth and by the power of the Holy Spirit break through our bias and personal delusion of self-sufficiency. This will allow us to begin to see from the heavenly perspective—as He sees all in and around our lives.