Passage
So if any one [be] in Christ, [there is] a new creation; the old things have passed away; behold all things have become new:
So if any one [be] in Christ, [there is] a new creation; the old things have passed away; behold all things have become new:
2 Corinthians 5:15 and he died for all, that they who live should no longer live to themselves, but to him who died for them and has been raised.
2 Corinthians 5:16 So that *we* henceforth know no one according to flesh; but if even we have known Christ according to flesh, yet now we know [him thus] no longer.
2 Corinthians 5:17 So if any one [be] in Christ, [there is] a new creation; the old things have passed away; behold all things have become new:
2 Corinthians 5:18 and all things [are] of the God who has reconciled us to himself by [Jesus] Christ, and given to us the ministry of that reconciliation:
2 Corinthians 5:19 how that God was in Christ, reconciling the world to himself, not reckoning to them their offences; and putting in us the word of that reconciliation.
The verse centers on "all things", "christ", "creation", "passed", "away", "behold", and "become". It is saying that the verse draws attention to "all things" and "christ", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 16's "So that we henceforth know no one..." into verse 18's "and all things are of the God...", so "all things" and "christ" belong inside that flow. In 2 Corinthians context, the local focus is Christ, faith, and discipleship.
A plain takeaway is to answer the verse's own emphasis on "all things" and "christ" with trust shaped by these words, not by a vague optimism outside the passage.