(I am not going to rattle on, but a few 4AM thoughts... they kind of link to a journal entry excerpt I shared earlier).
Sanctification is tricky, at least in my mind. The concept is simple, but the actionable data is hazy at best. Anyway, I have been thinking about it (because nothing is more jolly than thinking about things that make you feel dumb, derp).
As an example of suffering and patience, brothers, take the prophets who spoke in the name of the Lord. Behold, we consider those blessed who remained steadfast. You have heard of the steadfastness of Job, and you have seen the purpose of the Lord, how the Lord is compassionate and merciful.
Through the processes of chronic illness, God has been sanctifying me. Not to say that when I felt healthy He wasn't, but rather... It might be best explained as the realization that trials are not useless. So, I am amazed to be able to say that I am counting it all joy, praying that it produces steadfastness, and that I am humble to "let steadfastness take its full effect", so that I may be "perfect and complete, lacking in nothing" (James 1:2-4).
At the risk of sounding glib (and please know I am sincere)... I'd rather be sick and being sanctified than be healthy and not being sanctified. And yes, there is a third option (being healthy while being sanctified). But honestly, who cares? It is irrelevant to the idea. Third option or no, whatever God can use to sanctify me so that I can be useful to Him and live to the praise of His glory... that is a mercy, a kindness I do not merit. The fact that God, creator of the universe, who has already paid the immeasurable cost of my unfaithfulness & sin and then saved me unto Himself chooses to be involved and loves me (us!) enough to sanctify me is amazing. Sickness is a part of the fall, an imperfection that is the result of sin. But, if He can use the fruit of the fall to plant a tree of life within me...that is marvelous indeed.
So we do not lose heart. Though our outer self is wasting away, our inner self is being renewed day by day.
2 Corinthians 4:16
An amazing, merciful gift. The thankfulness is bursting from my heart. He is gloriously perfect and yet He chooses to work to make me more holy. How can I restrain my praises? My thankfulness? My wonder? "For this light momentary affliction is preparing for us an eternal weight of glory beyond all comparison, as we look not to the things that are seen but to the things that are unseen. For the things that are seen are transient, but the things that are unseen are eternal." (2 Corinthians 4:17-18)